  In this paper we generalize Kaplansky's combinatorial characterization of the
isomorphism types of embeddings of a cyclic subgroup in a finite abelian group
given in his 1951 book ``Infinite Abelian Groups''. For this we introduce
partial maps on Littlewood-Richardson tableaux and show that they characterize
the isomorphism types of finite direct sums of such cyclic embeddings.
