Conditions for bifurcations of solutions of degenerate boundary-value problems. Neliniini Kolyvannya, [S. l.], v. 12, n. 2, p. 147–154, 2009. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/516. Acesso em: 21 jan. 2026.