%0 Journal Article %A Doroslovački Rade %A Tošić Ratko %T A characterization of hexagonal systems %J Novi Sad Journal of Mathematics %D 1984 %P 201-209 %V 14 %I mathdoc %U http://geodesic.mathdoc.fr/item/NSJOM_1984__14__a18/ %F NSJOM_1984__14__a18