Which mathematician was the father of physicist Nikolai Borisovich Delone: Jakow Trachtenberg or Boris Delaunay?
Jakow Trachtenberg Jakow Trachtenberg (17 June 1888 – 1953) was a Jewish mathematician who developed the mental calculation techniques called the Trachtenberg system.
Leonid Pasternak Leonid Osipovich Pasternak (born "Yitzhok-Leib", or "Isaak Iosifovich, Pasternak"; Russian: Леони́д О́сипович Пастерна́к , 3 April 1862 N.S. – 31 May 1945) was a Russian post-impressionist painter. He was the father of the poet and novelist Boris Pasternak.