2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/159612The main contribution of our paper is to give a partial classification of the quasi-exactly solvable Lie algebras of first order differential operators in three variables, and to show how this can be applied to the construction of new quasi-exactly solvable Schrödinger operators in three dimensions.Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/Differential GeometryMathematical PhysicsExactly Solvable and Integrable Systems81Q70, 22E70, 53C80text