Schichtengleiche Gewichte und Butlergruppen
Self-cancellation of torsion-free Abelian groups of finite rank.
Splitting in abelian groups
Splitting of pure subgroups
Square subgroups of rank two abelian groups
Let G be an abelian group and ◻ G its square subgroup as defined in the introduction. We show that the square subgroup of a non-homogeneous and indecomposable torsion-free group G of rank two is a pure subgroup of G and that G/◻ G is a nil group.
Strong -groups
Subquadratic growth of the averaged Dehn function for free Abelian groups.
Sur les groupes quasi-purs-projectifs sans torsion