ZHANG, Lingling; WANG, Hui; WANG, Xiaoqiang. Fixed point results in set $P_{h,e}$ with applications to fractional differential equations. Topological Methods in Nonlinear Analysis, [S. l.], v. 54, n. 2, p. 536–566, 2019. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2019.052. Acesso em: 8 jul. 2025.