Were Pavel Urysohn and Leonid Levin known for the same type of work?
Pavel Urysohn Pavel Samuilovich Urysohn (Па́вел Самуи́лович Урысо́н ) (February 3, 1898 – August 17, 1924) was a Soviet mathematician of Jewish origin who is best known for his contributions in dimension theory, and for developing Urysohn's Metrization Theorem and Urysohn's Lemma, both of which are fundamental results in topology. His name is also commemorated in the terms Urysohn universal space, Fréchet–Urysohn space, Menger–Urysohn dimension and Urysohn integral equation. He and Pavel Alexandrov formulated the modern definition of compactness in 1923.
Apollon Mokritsky Apollon Nikolayevich Mokritsky (Ukrainian: Аполлон Миколайович Мокрицький , "Apollon Mokrytskyi"; Russian: Аполлон Николаевич Мокрицкий , "Apollon Mokritsky", August 1810 – 1870) was a Russian-Ukrainian painter of the Biedermeier period of Realist art. From 1849, he was a full member of the Saint Petersburg Academy of Arts.