@article{00528835, title = {Commutativity theorem for }, journal = {Mathematica Pannonica}, volume = {4}, year = {1993}, pages = {181-190}, zbl = {0796.16027}, language = {en}, url = {http://dml.mathdoc.fr/item/00528835} }
Abujabal, Hamza A.S.; Perić, Veselin. Commutativity theorem for . Mathematica Pannonica, Tome 4 (1993) pp. 181-190. http://gdmltest.u-ga.fr/item/00528835/