@article{01354932, title = {The two-parameter operators.}, journal = {Mathematica Pannonica}, volume = {9}, year = {1998}, pages = {243-258}, zbl = {0929.42017}, language = {en}, url = {http://dml.mathdoc.fr/item/01354932} }
Eisner, Tímea. The two-parameter operators.. Mathematica Pannonica, Tome 9 (1998) pp. 243-258. http://gdmltest.u-ga.fr/item/01354932/