Global solvability of one degenerate semilinear differential-operator equation. Neliniini Kolyvannya, [S. l.], v. 7, n. 3, p. 414–429, 2004. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/318. Acesso em: 21 jan. 2026.