M. Klaus, J. Schwerdtfeger, und R. Wagner. Consumer Citizenship Network: Making a Difference - Putting Consumer Citizenship into Action, Seite 163 -- 177. Berlin, The Consumer Citizenship Network, an Erasmus thematic network of educators and researchers, (2009)
M. Klaus, J. Schwerdtfeger, und R. Wagner. Proceedings of the 38th EMAC Conference, Marketing and the Core Disciplines: Rediscovering References?, Nantes, (2009)
M. Parwoll, und R. Wagner. Aging Society and its Implications on Service Marketing Approaches in the Hospitality, Tourism and Transport, Bock, Bad Honnef, (2011)