Alyabieva В. Г. International Congress of Mathematics. CHICAGO. 1893. BULLETIN OF PERM UNIVERSITY. MATHEMATICS. MECHANICS. COMPUTER SCIENCE, [S. l.], n. 1(52), p. 89–97, 2021. DOI: 10.17072/1993-0550-2021-1-89-97. Disponível em: http://press.psu.ru/index.php/Math/article/view/5038. Acesso em: 18 may. 2024.