“…The systematic study of them had been started with seminal papers [9] were the competed classification of the second order integrals of motion for the 2d Schrödinger equation was proposed. These results induced a great many of generalizations, staring with 3d models [10], [11] and continuing with models including matrix potentials [12,13,14] and the higher (and even arbitrary) order integrals of motion [15,16,17,18]. Moreover, such generalizations include the systems more generic than the standard Schrödinger equations, namely, Schrödinger equations with position dependent mass (PDM).…”