%0 Journal Article
%A F. Halter-Koch
%T Arithmetical semigroups defined by congruences.
%J Semigroup forum
%D 1991
%P 59-62
%V 42
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/SF_1991__42_3_135064/
%F SF_1991__42_3_135064