%0 Journal Article %A M.J. Pelling %T Subadditive functions on modules and subgroups of abelian groups. %J Aequationes mathematicae %D 1989 %P 15-37 %V 37 %N 2-3 %I mathdoc %U http://geodesic.mathdoc.fr/item/AM2_1989__37_2-3_137293/ %F AM2_1989__37_2-3_137293