On the average number of direct factors of a finite abelian group (“sur les variété abéliennes”) Hartmut Menzer — 1995 Journal de théorie des nombres de Bordeaux
On the Average Number of Direct Factors of a Finite Abelian Group. Hartmut Menzer; René Seibold — 1990 Monatshefte für Mathematik
On an asymmetric divisor problem with congruence conditions. Werner Georg Nowak; Hartmut Menzer — 1989 Manuscripta mathematica