@article{NSJOM_1992_22_2a_13,
     author = {Hamza A. S. Abujabal},
     title = {Some commutativity 

 properties for rings},
     journal = {Novi Sad Journal of Mathematics},
     pages = {163-175},
     publisher = {mathdoc},
     volume = {22},
     number = {2},
     year = {1992},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1992_22_2a_13/}
}