Some coincidence theorems in wedges, cones, and convex sets
Coincidence degree is used to study the solvability of a semilinear equation in a prescribed convex set. Generalizations of the Schauder fixed point theorem and compression theorem by Krasnosel'skij are given. The author applies some of the abstract results to establish existence of nonnegative solutions to some boundary value problems involving ordinary differential equations.
scientific article; zbMATH DE number 3920987