%0 Journal Article %A Siniša Crvenković %A Vladimir Tasić %T Second cohomology and nilpotency class 2 %J Publications de l'Institut Mathématique %D 2007 %P 3 %V _N_S_81 %N 95 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.2298/PIM0795003C/ %R 10.2298/PIM0795003C %G en %F 10_2298_PIM0795003C