The fate of two mathematicians: father and son Yakov and Mikhail Perelman

For the first time, the results of scientific work of Yakov Isidorovich Perelman (1882–1942) in the field of mathematics and its applications to the theory of elasticity are described. These results were obtained in 1939–1941 under the leadership of academician B.G. Galerkin (1871–1945). It will also talk about the life of Mikhail Yakovlevich Perelman (1919–1942) and his scientific results in the field of analysis (published) and topology (not published), which he received under the guidance of professor A.A. Markov Jr. (1903–1979).
Author's amendment of 01/31/2023. I inform you that since 1947 Perelman Yakov Isaevich, who was born in 1900 in Minsk and graduated in 1934 in mathematics and mechanics faculty of Leningrad university, candidate of physical and mathematical sciences (1940) and at the same time received the title of associate professor, was a student of academician Galerkin. The article in the PMM journal, analyzed in my book, belongs to him. Bottom line: I was wrong in attributing the article to Yakov Isidorovich Perelman.