@article{NSJOM_2008_38_3a_4,
     author = {Z. Z. Petrovi\'c and S. M. Moconja},
     title = {On graphs

 associated to rings},
     journal = {Novi Sad Journal of Mathematics},
     pages = {33-38},
     publisher = {mathdoc},
     volume = {38},
     number = {3},
     year = {2008},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_2008_38_3a_4/}
}