1. Christiansen, K., Grove, A., Hansen, L.E., Hoffman, L., Jensen, A.A., Pommer, P. and Schmidt, A. ‘Environmental Assessment of PVC and Selected Alternative Materials’, Miljöstyrelsen, Copenhagen, Danish version 1990, English version in press
2. Product Life Cycle Assessment - Principles and Methodology,1992
3. Substitution of dangerous chemicals—the solution to chemical health hazards in the work environment?;Antonsson;Am. Ind. Hyg. Assoc. J.,1995
4. Guidelines for Life-Cycle Assessment: A “Code of Practice” from the workshop held at Sesimbra,1993
5. Product Life Cycle Assessment - Principles and Methodology;Lindfors,1992