de Mattos, Denise, and Edivaldo L. dos Santos. “On Nonsymmetric Theorems for $(H,G)$-Coincidences”. Topological Methods in Nonlinear Analysis 33, no. 1 (March 1, 2009): 105–119. Accessed July 22, 2024. https://apcz.umk.pl/TMNA/article/view/TMNA.2009.008.