In memoriam: Leo Sario, Professor Emeritus, 1916 – 2009

Professor Emeritus Leo Sario died of a heart attack at his Santa Monica home on August 15, 2009. He was 93. In Finland during World War II, Sario was recognized as an excellent teacher and officer who made key contributions to the defense of the country, all while diligently pursuing his mathematical studies. After the war, Sario received his PhD under Rolf Nevanlinna and helped to establish the National Academy of Finland. Moving to the U.S. in the 1950s, he worked at Princeton, MIT, Stanford and finally UCLA, from which he retired in 1986. Sario created the theory of principal functions and wrote five major books including Riemann Surfaces with Lars Ahlfors, Classification Theory of Riemann Surfaces with M. Nakai, and Principal Functions with Burton Rodin. He also published over 130 research papers and mentored 36 doctoral students.