1. ISO 14040. Environmental management—life cycle assessment—principles and framework; 1997.
2. ISO 14041. Environmental management—life cycle assessment—goal and scope definition and inventory analysis; 1998.
3. ISO 14042. Environmental management—life cycle assessment—life cycle impact assessment; 2000.
4. ISO 14043. Environmental management—life cycle assessment—life cycle interpretation; 2000.
5. ITC. Production and utilization of biofuels derived from vegetable oils. Document of the Italian Thermo-Technical Committee. Lombardia Region. Italian; 2000. Available from: http://www.cti2000.it/virt/cti2000/headbio.html [accessed April 2005].