Expertensystem zur Beurteilung von Werbestrategien. - Thomas Levermann (Gabler, 1995)

CRM Systems in German Hospitals: Illustrations of Issues & Trends. - Mahesh S. Raisinghani; E.-Lin Tan; Jose Antonio Untama; Heidi Weiershaus; Thomas Levermann; Natalie Verdeflor (J. Cases Inf. Technol., 2005)