Abelian p-groups of arbitrary length and their endomorphism rings

Abstract

The second author enjoyed listening to many brilliant lectures on pure and applied mathematics by Professor G. Köthe at Frankfurt University. Gottfried Köthe refereed Ulm's Habilitationsschrift in 1936 and in 1988 he helped completing the paper [«Helmut Ulm: His work and its impact on recent mathematics», by R. Göbel, pp. 1-10 in Contemporary Mathematics vol. 87 (1989)].This paper which deals with abelian p-groups of arbitrary infinite Ulm length is dedicated to the memory of Gottfried Köthe.