RT Journal Article T1 Fixed point index theory for decomposable multivalued maps and applications to discontinuous ϕ-Laplacian problems A1 Precup, Radu A1 Rodríguez López, Jorge K1 Fixed point index theory K1 Discontinuous differential equation K1 Multiple solutions K1 ϕ-Laplacian equation K1 Lower and upper solutions AB In this paper, we develop a fixed point index theory for decomposable multivalued maps, that is, compositions of two multivalued nonlinear upper semicontinuous maps. As an application, this fixed point index theory is combined with the method of lower and upper solutions in order to obtain new existence, localization and multiplicity results for ϕ-Laplacian problems with discontinuous nonlinearities and nonlinear functional boundary conditions. PB Elsevier SN 0362-546X YR 2020 FD 2020 LK https://hdl.handle.net/10347/44794 UL https://hdl.handle.net/10347/44794 LA eng NO Nonlinear Analysis Volume 199, October 2020, 111958 NO Jorge Rodríguez-López was financially supported by Xunta de Galicia, Spain under grant ED481A-2017/178 and partially supported by Ministerio de Economía y Competitividad, Spain, and FEDER, Spain, Project MTM2016-75140-P, and Xunta de Galicia, Spain ED431C 2019/02. DS Minerva RD 8 jun 2026