Joel Smoller, 1936-2017
Joel Smoller, 81, passed away September 27, 2017, after a prolonged illness. He was born and raised in Brooklyn, the son of a New York City taxi driver. Despite the hardship of losing his mother at an early age, and with the support of his extended family, he pursued academics in the public schools. He found his love of math in his first geometry course in high school, and then never waivered in his desire to become a mathematician. He attended NYU for his undergraduate degree, and Purdue for his PhD in 1963.
His first and only academic appointment was at University of Michigan Department of Mathematics. His 54 year career here began in 1963 as an instructor. Smoller was promoted to professor in 1970, and was named the Lamberto Cesari Collegiate Professor of Mathematics in 1998. He retired from active faculty status in June, 2017. Smoller’s long and prestigious academic career includes supervising 28 graduate students and mentoring many postdoctoral faculty, producing more than 180 publications in association with 34 co-authors, and teaching hundreds of undergraduate and graduate students.
He specialized first in partial differential equations, but his research regularly grew into different fields as a new passion took hold. He conducted research in shock-wave theory; Navier-Stokes equations; systems of reaction-diffusion equations; stellar dynamics; dynamical systems (Conley Index Theory); and bifurcation theory (symmetry-breaking bifurcations). He pioneered the analysis of numerical difference schemes for conservation laws in several space dimensions, introduced new topological methods to the analysis of partial differential equations, and was fundamental in establishing the shock structure problem in mathematics. Many of his early results have been influential in mathematical biology. Smoller's more recent research concerned Stability of Kerr (rotating) Black Holes under various perturbations such as scalar waves, Dirac Fields, electromagnetic waves, and gravitational waves; and astrophysical shock-waves, concerned with astrophysical problems including an explanation of the anomalous acceleration of the Universe, wholly within Einstein’s equations of General Relativity and avoiding the cosmological constant, and the notion of dark energy. His book, "Shock Waves and Reaction—Diffusion Equations" became the standard in that area and has been a reference in programs worldwide.
During his career, Smoller received significant recognition for his scholarly activities including a Guggenheim Fellowship in 1980, the Margaret and Herman Sokol Award in 1992, and an Excellence in Research Award in 1996. More recently he was named a senior Humboldt Fellow, and received the prestigious G.D. Birkhoff Prize in Applied Mathematics from AMS/SIAM in 2009. The Birkhoff prize is awarded jointly by the American Mathematical Society and the Society for Industrial and Applied Mathematics once every three years to recognize an outstanding contribution to "applied mathematics in the highest and broadest sense." There, Smoller was cited for his leadership, originality, depth and breadth of work in dynamical systems, differential equations, mathematical biology, shock wave theory and general relativity. Three special issues of the journal, Methods and Applications of Analysis were dedicated to him and featured a photograph of him on the front covers.
From his home base at Michigan, Joel became a citizen of the world. He loved to travel and meet new people, and was a frequent speaker at international conferences and seminars. Over his career, he was also a visiting member at Courant Institute of Mathematical Sciences, and a visiting professor at the University of Wisconsin, the University of Paris, and Ecole Normale Superieure, in Paris. He spent sabbatical leaves at the University of Warwick, Harvard University, and University of California, Davis.
Joel had a passion for math and would sometimes spend spare time returning to some problem on his desk. He also spent significant time on the tennis and squash courts. He continued to jog and to play squash until a serious injury slowed him down. Even then, he kept up a regular exercise program and would not be stilled. He was also known for his subtle and appreciative sense of humor. He was a kind, giving individual with an endearing quirkiness, who was only ferocious about math and politics.
He loved to spend time at the lake in summer and Florida in the winter, and enjoyed entertaining, and hosting people in his home. He valued his family above all, and had a great enthusiasm for life. He was happiest when surrounded by family and friends, enjoying good food and wine in their company.
Joel is survived by his wife Margaret, children, Debbie, Alex (Lisa Mitchell), and Sally; his stepchildren Anne Dickinson (Patrick) and David Arditti; his granddaughter, Arcadia Mitchell; his brother Howard, and his many friends, coauthors, and colleagues here and abroad.
Joel's research was funded by NSF grants for almost his entire career, and he supported many students to the maximum possible. He leaves behind a large number of math professors and professionals whom he nurtured and mentored through their academic training and into their careers; many began as students and ended as close friends and coauthors. He cared deeply about mentoring and supporting his students. To carry on this tradition, a scholarship has been established in his name to benefit graduate mathematics students working in his area of expertise, partial differential equations associated with physical processes. Memorial contributions can be made to the Joel Smoller Fellowship Fund in the Department of Mathematics (fund #700262). Contributions can be sent via mail to the UM Department of Mathematics, 530 Church Street, Ann Arbor, MI 48109-1043 (checks to University of Michigan), or online at the following link: http://victo.rs/2y3Yohi.
Maxwell O. Reade, 1916-2016
After 100 years and two days, Professor Emeritus Maxwell O. Reade died April 13.Maxwell ReadeHe met his goal of living to 100, and he led a remarkable life. The son of Hungarian immigrants, Reade was born in Philadelphia, and later moved with his family to Brooklyn, where he finished high school and attended Brooklyn College, graduating in 1936. He entered the math graduate program at Harvard on tuition scholarship, then went to Rice University on full scholarship to get his Ph.D. in 1940.
Reade was a professor of mathematics at the University of Michigan for 40 years, specializing in Complex Analysis, published 83 papers and was awarded the AMOCO Good Teaching Award in 1983. In World War II, he worked for the Applied Mathematics Panel of the Office of Scientific Research and Development and his applications of mathematics to the Allied war effort saved thousands of lives.
As associate chairman for mathematics graduate students for over seven years in the late 1960s and early 1970s, Reade was both a vigorous recruiter of quality students and a tireless worker on their behalf once they were here. He was ahead of his time in recognizing the importance of seeking and nurturing minority students. Reade ardently supported scholarships and grants for students, traveling to historically black colleges in the South and recruiting students for scholarships — more than 50 Ph.D.s were awarded to minority students he recruited — as well as foreign students. These trips afforded an opportunity to indulge in his passion for jazz, and he interviewed many musicians while amassing a large collection of jazz records.
As chairman of the LSA Scholarship committee from 1974 to 1994, Reade continued to help countless students pursue a college education who would not have otherwise had the means. He found and recruited talented students in all disciplines and was instrumental in establishing the Dean’s Merit Scholarships in LSA. He had the ability to seek and find extremely bright students, particularly in mathematics, and convince them that Michigan was the right choice for their education. Reade was especially effective in assuring the mothers that their children would succeed here. His warmth, humor and passion for Michigan became the deciding factor for many to choose Michigan.
Reade was predeceased by his wife Marjorie and his former wife Isabel. He is survived by children Michael, Tim (Joy) and Alison Diver, and Lawrence Dolph (Lynn Nybell); grandchildren Fran (Ben Rosenberg), Chris, Wes Diver, Christine Dolph (Brian Wachutka) and John Dolph; great-granddaughter Winona Marjorie Wachutka; nieces Pam Schwarzmann (Ken Fink), Karen Schwarzmann (Larry Rosen) and Ann Schwarzmann (Greg Haagenson); nephews Tom Schwarzmann (Lisa Byle) and Tim Schwarzmann; grand nephew Peter Griess (Tiffany Reese); and great-grand nephew Ryder Griess.
Reade was known for his sense of humor, devotion to causes supporting the "little guy," intolerance of social injustice, making paw paw jam and writing letters to the editor published in the New York Times and Ann Arbor News. His final gift to education was to donate his brain to a longitudinal study at the U of M Brain Bank.
Memorial contributions may be made to the Maxwell and Marjorie Reade Fund for Student Support via the University of Michigan online giving site.
Peter Smereka, 1959-2015
Peter Smereka passed away September 15, 2015, after suffering a heart attack. Born in Sault Ste. Marie, Ontario to Virginia and Edward Smereka, he was the first of four children. He attended Aurora High School in Aurora, Ontario (1974-1978) where he was valedictorian of his class. He participated very actively in Ontario science fairs, winning the Canada-wide science fair competition for three consecutive years.
In 1983, Smereka received his bachelor’s degree in Physics from the University of Waterloo, Canada. He received his Ph.D. in Chemical Engineering from the University of California, Santa Barbara, in 1989. After visiting the Courant Institute of Math at NYU, and the Institute for Mathematics and its Applications, Smereka joined the faculty of the Department of Mathematics at the University of California, Los Angeles, in 1991 on an NSF postdoctoral fellowship.
Smereka came to the UM Mathematics Department in 1994 as an assistant professor. He was promoted to associate professor in 1997, and professor in 2003. He was also active as a member of the Michigan Center for Theoretical Physics. Smereka was an early and integral member of the Department’s Applied and Interdisciplinary Mathematics (AIM) program, providing an important link with areas of engineering and the natural sciences. He served as director of the AIM program for several years. He received a prestigious NSF Career Award in 1996, and an Excellence in Education Award from the College of Literature, Science and the Arts in 1997. Smereka was one of the original developers and instructors of a new honors sequence for first-year science and engineering students. He served the Department through numerous committee assignments, undergraduate counseling, and research coordination.
Considered one of the leading applied and computational mathematicians of his generation, Smereka worked on a wide variety of problems, ranging from fluid dynamics to materials science. His early work had great effect on problems in “bubbly liquid flow” and he was widely regarded as the leading authority on this subject. His work on algorithms for multi-phase flow—for example, for simulating the motion of two immiscible fluids and the surface that separates them—has been particularly influential. In that field, and more generally in the topic of interfacial motion, Smereka made fundamental contributions. The algorithms he invented and helped develop are used in many branches of science and engineering. Many of his more than 60 research articles and numerous conference proceedings have had tremendous impact, and some are considered classics in their respective fields. In addition to being a leading authority in computational mathematics, applying his extensive knowledge of Physics and Engineering to mathematical modeling and computational simulation of physical problems, Smereka also excelled as an applied analyst, exploring the associated mathematical problems in great depth. In 2009, he was part of a team that received a patent for “a method for designing aerosol spray dispensers.” During his career Smereka supervised six Ph.D. students and acted as a co-advisor for many others.
Smereka was always inquisitive and he provided a lot of humor, insight and thought-provoking questions for his family and colleagues over the years. He was an incredibly sensitive and kind person often running to help his family members when in need. Smereka loved to surf, hike, listen to jazz and eat street food, and play games. He also enjoyed golfing and swimming, and loved watching Stephen Colbert and Jon Stewart with his son Aidan. Smereka is survived by his wife Brenda, son Aidan, parents Ed and Virginia, sisters Karen and Susan, brother Robert and Aunt Joan, as well as many friends and colleagues from all over the world. He will be greatly missed by all. Memorial notes may be sent to firstname.lastname@example.org.
The Department of Mathematics has established the Peter Smereka Memorial Graduate Student Prize. Memorial donations may be made via the University of Michigan online giving site.
Donald J. Lewis, 1926-2015
Donald J. Lewis, Professor Emeritus of Mathematics at the UM, passed away on February 25, 2015 at the age of 89. Born in Minnesota, to William and Eleanor Lewis, he was the oldest of eight children. He married Carolyn Dana Hauf in 1953 in Ann Arbor. He received his B.S. from the College of St. Thomas in 1946, and his M.S. and Ph.D. from UM, respectively in 1949 and 1950.
Lewis joined the University of Michigan faculty as an associate professor in 1961, and was promoted to full professor in 1963. He served as Chair of the Department of Mathematics at UM during the period 1984 to 1994, with a break for one year to visit the Institute for Advanced Study. He was also noted for his leadership in University affairs, and received numerous awards for his research and service, including a Distinguished Faculty Achievement Award from UM and an Alexander Von Humboldt Preis. Even after retirement from UM in 2000, Lewis was active in research and continued to work in the department on alumni relations and fundraising.
Between 1995 and 1999, Lewis was based in Washington, D.C. as the Director of the Division of Mathematical Sciences of the National Science Foundation. While at NSF, he championed multidisciplinary initiatives that paved the way for the applied and interdisciplinary mathematics programs that are thriving at universities around the country. Lewis also developed and promoted vertical integration of mathematical research at the university level. He was awarded the Distinguished Public Service Award of the American Mathematical Society in 1995 in recognition of his many contributions to mathematics research and education.
Lewis’ research was in an area of Number Theory concerned primarily with Diophantine problems, and encompassed the theory of algebraic number fields and arithmetic geometry. While a number of his results have been improved in recent times, it is characteristic especially of his earlier work that he was the first to obtain any kind of result on a problem, and that this decisive progress cleared the way for subsequent developments. The work in his thesis concerning local solubility of cubic forms, however, remains definitive. Also noteworthy is a series of papers produced in a longstanding collaboration with Harold Davenport which laid the foundations for the investigation of a number of Diophantine problems, especially diagonal variants.
In 1966, Lewis authored the book “Introduction to Algebra” that utilized the art of M.C. Escher to help display mathematical concepts and illustrate the interplay between the two disciplines. He published two volumes of the book “Calculus and Linear Algebra” with UM colleague Wilfred Kaplan, which have recently been reprinted and used in courses at UM. He is the author of 58 research papers and a number of survey papers. The latter, in particular, have provided valuable stimulation to a generation of workers in this field. One of Lewis’ main interests was the development of young mathematicians and he directed 24 doctoral theses.
Memorial contributions may be made to the Donald J. Lewis Professorship in Mathematics (571193) Donations may be made via the University of Michigan online giving site.
Curtis Huntington, 1942-2013
Long time factuly member, Actuarial Program Director and Associate Chair for Education Curtis Huntington passed away in October 2013 after a three-year battle with cancer.
Born in Boston in 1942, Huntington’s father was an actuary and his mother was also a mathematician. He received a BA in mathematics in 1964, and an MA in business in 1965, both from UM, and later received a JD from Suffolk University. After completing service as a commissioned officer in the U.S. Public Health Service, Huntington joined the New England Mutual Life Insurance Co. (Boston), where he served from 1967 until his retirement in 1993 as a Vice President and Corporate Actuary.
During his distinguished career, he was named a fellow of the Society of Actuaries (FSA 1968), a member of the American Academy of Actuaries (MAAA 1972), a fellow of the Conference of Consulting Actuaries (FCA 2001), and an associated professional member of the American Society of Pension Professionals and Actuaries (APM 1990). His service to the actuarial community was monumental, and he helped to guide and shape the profession internationally for many years. Huntington was recognized for his distinguished career and tireless service to the profession. He was the 2010 recipient of the Harry T. Eidson Founders Award from the American Society of Pension Professional and Actuaries, and he also received the Jarvis Farley Service Award from the American Academy of Actuaries for his distinguished service to the actuarial profession through his numerous volunteer efforts during his career. In 2012, he received the Lifetime Achievement Award from the Conference of Consulting Actuaries.
In 1993, Huntington returned to UM as a Professor of Mathematics and Director of the Actuarial Mathematics Program and the Financial Mathematics Program. He served two terms as the associate chair for education in the Department, including the three years prior to his passing. He chaired the scholarship committee, assuring that students who needed tuition support received help. Huntington also arranged, proctored, and helped to fund the actuarial exams for students. He was instrumental in the significant increase of graduates from the actuarial/financial mathematics program over the past two decades. He helped to expand the program to include a financial component, increased the number and quality of the faculty members in the area, and increased the activities for the students. Huntington was proud of the active Student Actuaries at Michigan (SAM) group and guided them in organizing employ-er recruiting, professional development activities, and social events. He would excitedly share the successes of the SAM intermural teams in sports including broomball and water polo.
Huntington worked tirelessly on the development and fundraising activities of the Department, and served as the Development Committee chair for several years. He formed the Actuarial Alumni Leadership Council, which helps to guide and support the program. He personally endowed a fund in his mother’s name that recognizes outstanding students in mathematics. He was the driving force in a successful campaign to endow a professorship in honor of Professor Cecil Nesbitt. When students graduated from the actuarial/financial mathematics program, they were instilled with Huntington’s philanthropic spirit. He encouraged them to support UM as soon as they had the means, and he led by example. Several years ago, Huntington’s colleagues at UM and from the actuarial profession established the Curtis E. Huntington Honorary Fund to provide support to the students and programs within actuarial/financial mathematics.
Even during his illness, Huntington found the time to lead and promote the actuarial profession around the world. His national and international travel schedule was packed with lectures, board meetings, and conferences. During his extensive travels, he made time to visit his other homes in Boston and New Zealand. He forged many personal friendships around the world, and made time for anyone who needed him. A memorial service for Huntington was held at the Michigan Union in April 2014. More than 150 friends and colleagues joined to celebrate Huntington’s life and contributions to the Actuarial profession and the UM. Personal memories were shared by many friends and colleagues. His sister, Peg, and her husband, Hugh, traveled from New Zealand to host the ceremony. Memorial contriubtions have been made to the Curtis E. Huntington Honorary Fund in the Department of Mathematics (allocation 572235). The Department recently received $2 million from Huntington’s estate. The funds will be used to continue the activities within the Actuarial and Financial Mathematics program. Donations may be made via the University of Michigan online giving site.
Frederick Gehring, 1925-2012
Distinguished University Professor Emeritus Fredrick W. Gehring passed away on May 29, 2012 at age 86. Born in Ann Arbor, his association with the University of Michigan went back two generations to his grandfather, John Oren Reed, who was a member of the physics faculty and Dean of the College of Literature, Science and the Arts. Gehring joined the U.S. Navy in 1943 and subsequently earned two degrees from UM—Bachelor of Science in mathematics and electrical engineering in 1946, and Master of Science in mathematics in 1949. After completing his Ph.D. at the University of Cambridge (England) and spending three years as a Benjamin Peirce Instructor at Harvard, he returned in 1955 to teach mathematics at UM. He was promoted to the rank of Professor in 1962, was named to a collegiate chair in 1984, and became the T. H. Hildebrandt Distinguished University Professor in 1987. His long history of service at UM includes three terms as chair of the Department of Mathematics. He retired in 1996.
Gehring was a leading figure in the theory of quasiconformal mappings. Briefly, these mappings of the plane send infinitesimal circles to infinitesimal ellipses with bounded eccentricity. Fulbright and Guggenheim Fellowships in 1958–1960 allowed Gehring to study in Helsinki and Zürich, where he began to learn about quasiconformal mappings. He was instrumental in developing that theory, often in collaboration with Finnish colleagues, and bringing it into the mainstream of mathematical analysis. In particular, he pioneered an important extension of the planar theory to n-dimensional Euclidean space, emphasizing new tools such as extremal length. His work on the higher integrability of quasiconformal Jacobians lies at the foundation of the n-dimensional theory. In later years, largely in collaboration with his former student Gaven Martin, he brought quasiconformal mappings into a broad study of discrete transformation groups.
In 2006, the American Mathematical Society honored Gehring with a Steele Prize for Lifetime Achievement. The citation (Notices of the AMS 53 (2006), 468-469) says in part, “Largely because of Gehring’s work, the theory of quasiconformal mappings has influenced many other parts of mathematics, including complex dynamics, function theory, partial differential equations, and topology. Higher dimensional quasiconformality is an essential ingredient of the Mostow rigidity theorem and of recent work of Donaldson and Sullivan on gauge theory and four-manifolds…. Gehring’s mathematics is characterized by its elegance and simplicity and by its emphasis on deceptively elementary questions which later become surprisingly significant.”
Fred Gehring supervised twenty-nine Ph.D. students, many of whom are now faculty members at research universities, and he mentored more than forty postdoctoral fellows. He maintained contact with his former students and postdocs for many years and continued to inspire them with energy and enthusiasm for mathematics. Fred and his wife Lois took a personal interest in Fred’s students and postdocs, and brought many of them into their family circle. Two books coauthored with former students are now in final stages of preparation and will soon be published by the AMS.
In addition to the Steele Prize, Gehring’s many honors include the Humboldt Award, the UM Distinguished Faculty Achievement Award, Sokol Faculty Award, and Henry Russel Lectureship. He was named Commander of the White Rose of Finland. In 1989 he was elected to the American Academy of Arts and Sciences and to the National Academy of Sciences.
Fred was a devotee of fine wines and single malt whiskies. He loved classical music, foreign languages (he was remarkably fluent in Finnish), and camping. He is survived by his wife Lois, his sons Kalle and Peter, two grandchildren, and his sister Barbara Gehring. A memorial service was held in August 2012, attended by more than 100 people, including Fred’s graduate students from around the world.
Juha Heinonen , 1960-2007
Professor of Mathematics Juha Heinonen passed away on October 30, 2007, after a courageous battle with kidney cancer. Born July 23, 1960 in the small town of Toivakka in central Finland, Juha was raised in the village’s old-age home where his mother served as the sole staff member. His father Vilho was a lumberjack and well-respected socialist politician for the tiny town. After graduating high school, Juha served one year as an officer in the Finnish army, and then enrolled as a student of mathematics at the University of Jyväskylä. His 1987 Ph.D. thesis, directed by Olli Martio, was in non-linear potential theory.
Juha first came to the University of Michigan for a semester as a visiting graduate student in 1985. His first appointment in the Department of Mathematics began in 1988, when he returned as a three year post-doctoral assistant professor. In 1992 he accepted a tenure track assistant professorship, and in 2000 he was promoted to professor. He served as Associate Chair for Graduate Studies in the Department of Mathematics from 2004 to 2007.
Considered a scholar of high professional standards, Juha was a leading figure in geometric function theory, his main research area. His two books “Nonlinear Potential Theory of Degenerate Elliptic Equations” (co-authored with T. Kilpeläinen and O. Martio) and “Analysis on Metric Spaces" have become standard references in their fields. He co-authored more than 60 research papers, many of which contributed to the creation of a new branch of mathematics, now called analysis on metric spaces. Juha was a generous and enthusiastic collaborator who was proud of the fact that nearly all of his research publications were joint works. His collaborators admired him for his erudition, his deep mathematical insights, and his never-ending scientific curiosity.
Juha's expertise was recognized with many awards and fellowships, including a Sloan Fellowship, numerous NSF grants, several visiting appointments, and an Excellence in Research Award from the University of Michigan. For seven years he was an editor of the Proceedings of the American Mathematical Society. In 2002, he was invited to give a talk at the International Congress of Mathematicians in Beijing. Juha became a member of the Finnish Academy of Science and Letters in 2004.
A dedicated thesis advisor, Juha directed eight doctoral students. Many students, junior faculty, and young researchers greatly benefited from his patient mentorship and wise tutelage. Juha was very grateful for the excellent mentoring he himself received as a young mathematician, and was happy to repay in kind. In addition to his advisor, he especially acknowledged U-M Professor Emeritus Fred Gehring whom he met in 1985, and Jose Fernandez, to whom Fred introduced him later that academic year at the Mathematical Sciences Research Institute in Berkeley. Later he was deeply influenced by Dennis Sullivan who directed his attention to analysis in more abstract settings.
When Juha originally came to the United States, his intention was to stay for only a short period. His plans changed when he met his future wife, Karen Smith, a first-year graduate student of mathematics, who also arrived in Ann Arbor in the fall of 1988. They were married in 1991.
Juha put his own career on hold to follow his wife to Boston when she obtained a post-doctoral position at MIT. The couple came back to Ann Arbor as tenured professors in 1996, settling into a satisfying marriage and productive careers. They welcomed their daughter Sanelma in 1998, and their boy-girl twins, Tapio and Helena, in 2003.
A gifted athlete, Juha was the 1976 Finnish national champion in his class for 5 km cross-country skiing. Although he gave up professional sports to pursue a career in mathematics in the early 1980s, Juha's love of competitive sports never waned. He participated in many running, cross-country skiing and orienteering events around the country. In his class he won both the U.S. and the North American gold medal in orienteering in 2000.
Juha was a vibrant, balanced, satisfied person who enjoyed many things in life besides mathematics and sports. He spent his free time studying foreign languages, or reading history, biographies, and political commentary. He loved the outdoors, particularly Michigan autumns and Finnish winters. A devoted husband and father, Juha enjoyed the company of his children and was often spotted on errands around town with a child on the bus, on his bike-seat, or in his arms. Each time he spoke of his family, the pride was evident through the twinkle in his eye and his broad grin.
His Finnish origins remained deeply important to him throughout his life. Juha maintained close contacts with his Finnish friends and colleagues, and traveled to Finland at least once a year. He taught his children and his wife to speak Finnish and to share his love of his native land.
Juha was widely loved for his positive attitude, sparkling sense of humor, and genuine kindness towards others, traits that he maintained throughout the difficult trials of his illness. He is deeply mourned by his family, friends and colleagues. Besides his wife and children, Juha is survived by his mother Liisa Heinonen and his sister Maritta Nukarinen. A memorial service will be held at the Michigan League Ballroom on December 9 at 2 pm. The Department of Mathematics has established the Juha Heinonen Memorial Graduate Student Fellowship. Donations may be made via the University of Michigan online giving site.
"Quasiconformality in Metric Spaces" (.mov)
Dennis Sullivan's seminar, CUNY, November 1995
"Proceedings of American Math Society Heinonen Memorial issue. (see page 3)"