BEREZOVSKY, A. A.; KONET, I. M.; LENYUK, M. P.; SAMOILENKO, A. M.; TEPLINSKY, Yu. V. Ukrainian school-seminar "Nonlinear boundary value problems of mathematical physics and applications". Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 49, n. 4, p. 613–617, 1997. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5041. Acesso em: 5 dec. 2025.