Borsari, Lucilía D., and Daciberg L. Gonçalves. 2003. “Obstruction Theory and Minimal Number of Coincidences for Maps from a Complex into a Manifold”. Topological Methods in Nonlinear Analysis 21 (1):115-30. https://apcz.umk.pl/TMNA/article/view/TMNA.2003.007.