%0 Journal Article %A Imre Ruzsa %T Semigroup-valued multiplicative functions %J Acta Arithmetica %D 1982 %P 79-90 %V 42 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/aa-42-1-79-90/ %R 10.4064/aa-42-1-79-90 %G en %F 10_4064_aa_42_1_79_90