Branko Grünbaum

Branko Grünbaum (2 October 1929 – 14 September 2018) was a Yugoslavian-born American mathematician and a professor emeritus at the University of Washington in Seattle. He wrote over 200 papers, mostly in discrete geometry, an area in which he was known for many classification theorems. He has written on the theory of abstract polyhedra.
Grünbaum died in Seattle on 14 September 2018 at the age of 88