2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/78174Sergey Pinchuk found a polynomial map from the real plane to itself which is a local diffeomorphism but is not one-to-one. The aim of this paper is to give a geometric description of Pinchuk's map.LaTeX, 7 pages, 2 Postscript figuresAlgebraic Geometry14E07; 14E35text