National Museum of Nuclear Science & History
George Placzek was a Czech physicist. He was born in Brno, Moravia, which was then part of Austria-Hungary but today is in the Czech Republic.
Ralph Lapp was an American physicist. He was born in Buffalo, New York in 1917. He was completing his PhD at the University of Chicago when he stumbled upon Enrico Fermi’s team working under Stagg’s Field in December of 1942, and was hired on the spot to work on the development of the atomic bomb.