Nonlinear essential maps of Mönch, 1-set contractive demicopmact and monotone \((S)_+\) type (Q5952372)

The authors extended the notion of an essential map introduced by \textit{A. Granas} [C. R. Acad. Sci., Paris, Ser. A 282, 983-985 (1976; Zbl 0348.47039)] to a larger class of maps. They show if \(F\) is essential and \(F\cong G\), then \(G\) has a fixed point.