%0 Journal Article %A H.J. Weinert %T On left, right and two-sided cancellable elements of semigroups. %J Semigroup forum %D 1978 %P 97-104 %V 16 %I mathdoc %U http://geodesic.mathdoc.fr/item/SF_1978__16_134277/ %F SF_1978__16_134277