Rodríguez López, Jorge2022-11-112022-11-112022Nonlinear Analysis 226 (2023) 113138. https://doi.org/10.1016/j.na.2022.113138http://hdl.handle.net/10347/29409We present an alternative approach to the vector version of Krasnosel’skiĭ compression–expansion fixed point theorem due to Precup, which is based on the fixed point index. It allows us to obtain new general versions of this fixed point theorem and also multiplicity results. We emphasize that all of them are coexistence fixed point theorems for operator systems, that means that every component of the fixed points obtained is non-trivial. Finally, these coexistence fixed point theorems are applied to obtain results concerning the existence of positive solutions for systems of Hammerstein integral equations and radially symmetric solutions of (P1,P2) Laplacian systemseng© 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)Atribución 4.0 Internacionalhttp://creativecommons.org/licenses/by/4.0/Coexistence fixed pointFixed point indexPositive solutionHammerstein systemsp-Laplacian systemCoexistence fixed pointRadial solutionjournal article10.1016/j.na.2022.1131380362-546Xopen access