@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/