1. Directive 2006/40/EC of the European Parliament and of the Council of 17 May 2006 relating to emissions from air-conditioning systems in motor vehicles and amending Council Directive 70/156/EEC. Official Journal of the European Union. (161) June 14, 2006.
2. Emissions from air conditioning systems in motor vehicles. September 25, 2007. (accessed 05.10.10.).
3. Carbon dioxide - new uses for an old refrigerant;Pearson;International Journal of Refrigeration,2005
4. Lorentzen, G. Trans-critical vapour compression cycle device. Patent WO/07683. 1990.
5. A new, efficient and environmentally benign system for car air-conditioning;Lorentzen;International Journal of Refrigeration,1993