KANG, S.; CHENG, S. S. Positive periodic solutions of superlinear systems of integral equations depending on parameters. Topological Methods in Nonlinear Analysis, [S. l.], v. 27, n. 2, p. 387–398, 2006. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2006.015. Acesso em: 26 apr. 2024.