@article{05555871, title = {Intertwining symmetry algebras of quantum superintegrable systems.}, journal = {SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only]}, volume = {5}, year = {2009}, doi = {10.3842/SIGMA.2009.039}, zbl = {1161.37049}, language = {en}, url = {http://dml.mathdoc.fr/item/05555871} }
Calzada, Juan A.; Negro, Javier; del Olmo, Mariano A. Intertwining symmetry algebras of quantum superintegrable systems.. SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only], Tome 5 (2009) . doi : 10.3842/SIGMA.2009.039. http://gdmltest.u-ga.fr/item/05555871/