1. Heijungs R, Guinée JB, Huppes G, Lamkreijer RM, Udo de Haes HA, Wegener Sleeswijk A, Ansems AMM, Eggels PG, van Duin R, de Goede HP (1992): Environmental Life Cycle Assessment of Products. Guide (Part 1) and Backgrounds (Part 2), prepared by CML, TNO and B&G. Leiden October 1992. English Version 1993
2. Society of Environmental Toxicology and Chemistry (SETAC) (1993): Guidelines for Life-Cycle Assessment: A ‘Code of Practice’. From the SETAC Work-shop held at Sesimbra, Portugal, 31 March-3 April 1993. Edition 1, Brussels and Pensacola (Florida)
3. International Standard Organization (ISO) (1997): Environmental management — Life cycle assessment — Principles and framework. ISO 14040, June 1997
4. Habersatter K, Widmer F (1991): Oekobilanzen von Packstoffen. Stand 1990. In: Bundesamt für Umwelt, Wald und Landschaft (BUWAL), Bern (Hrsg): Schriftenreihe Umwelt Nr 132
5. Guinée J (2001): Handbook on Life Ccyle Assessment — Operational Guide to the ISO Standards. Editorial in Int J LCA 6 (5) 255