KORMAN, Philip; OUYANG, Tiancheng. Positivity for the linearized problem for semilinear equations. Topological Methods in Nonlinear Analysis, [S. l.], v. 28, n. 1, p. 53–60, 2006. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2006.019. Acesso em: 8 jul. 2025.