The topological transversality theorem for condensing mappings stated in  is used to prove some perturbation theorems: a theorem on \(\gamma\)-condensing perturbation of hyperaccretive mappings and a Browder type result on the perturbation of some bijective mappings \(\gamma\)-Lipschitz mappings. An application concerning the existence and the uniqueness of solution to a boundary value problem for nonlinear second order differential equations in Banach spaces is finally given.
Department of Mathematics, Babes-Bolyai University, Cluj-Napoca, Romania
R. Precup, Topological transversality, perturbation theorems and second order differential equations, Babeş-Bolyai Univ., Faculty of Math. Phys., Research Sem., Seminar on Differential Equations, 3 (1989), 149-164.
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