Andres, J. and Górniewicz, L. (1999) “From the Schauder fixed-point theorem to the applied multivalued Nielsen theory”, Topological Methods in Nonlinear Analysis, 14(2), pp. 229–238. Available at: https://apcz.umk.pl/TMNA/article/view/TMNA.1999.030 (Accessed: 19 January 2022).