Moser's Implicit Function Theorem in the Framework of Analytic Smoothing. Eduard Zehnder (1976) Mathematische Annalen
Mountain pass theorems and global homeomorphism theorems Guy Katriel (1994) Annales de l'I.H.P. Analyse non linéaire
M-T topologically stable mappings are uniformly stable. Hans Brodersen (1983) Mathematica Scandinavica
Multiple perturbed solutions near nondegenerate manifolds of solutions Michal Fečkan (1993) Commentationes Mathematicae Universitatis Carolinae The existence of multiple solutions for perturbed equations is shown near a manifold of solutions of an unperturbed equation via the Nielsen fixed point theory.