1. W. R. Stahel, "The Utilization-Focused Service Economy: Resource Efficiency and Product-Life Extension," in The Greening of Industrial Ecosystems, ed Washinton DC: National Academy Press, 1994, pp. 178-190.
2. A. Tukker and U. Tischner, New Business for Old Europe. Sheffield: Greenleaf Publishing, 2006.
3. M. J. Goedkoop, et al., "Product Service Systems, Ecological and Economic Basics," Dutch Ministry of Housing, Spatial Planning and the Environment, Hague VROM 990570, 1999.
4. J. C. Aurich, et al., "Life cycle oriented design of technical Product-Service Systems," Journal of Cleaner Production, vol. 14, pp. 1480-1494, 2006.
5. T. Sakao, et al., "Modeling Design Objects in CAD System for Service/Product Engineering," Computer-Aided Design, vol. 41, pp. 197-213, 2009.