By my editorial contributions, I filled most part of the contents of the issues 2/1989, 1/1990, 2/1990 of the magazine “PEARL-Mail”, published by Prof. Dr. L. Frevert,
Fachhochschule Bielefeld, IFE, Wilhelm-Bertelsmann-Straße 10, D-33602 Bielefeld, Germany. The issues were collected at the
Technische Informationsbibliothek und Universitätsbibliothek Hannover, Germany. Signature “ZO 7502”.