@article{NSJOM_1985_15_2a_11,
     author = {{\CYRYA}{\cyra}{\cyrn}{\cyre}{\cyrz} 

 {\CYRU}{\cyrsh}{\cyra}{\cyrn}},
     title = {{\CYRA}t -{\cyrk}{\cyrv}{\cyra}{\cyrz}{\cyri}{\cyrg}{\cyrr}{\cyru}{\cyrp}{\cyrp}{\cyrery}},
     journal = {Novi Sad Journal of Mathematics},
     pages = {141-154},
     publisher = {mathdoc},
     volume = {15},
     number = {2},
     year = {1985},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1985_15_2a_11/}
}