Stratmann, Jörg. Bedarfsgerechte Informationsversorgung im Rahmen eines produktlebenszyklusorientierten Controlling. Reihe, (Bd. 71) Eul, Lohmar, Köln, Year 2001.
Berkovich, M. and Leimeister, J. M. and Krcmar, H.. Suitability of product development methods for hybrid products as bundles of classic products, software and service elements. ASME 2009 - International Design Engineering Technical Conferences & Computers and Information in Engineering Conference IDETC/CIE. San Diego, USA, Year 2009.