1. American Society of Heating, Refrigerating, and Air-Conditioning Engineers, ASHRAE handbook of refrigeration, ASHRAE, Atlanta, USA, 2002.
2. CO2 systems are sweeping through the Netherlands;Lobregt,2003
3. Carbon dioxide based cascade systems for simultaneous refrigeration and heating applications;Sarkar,2004
4. The use of natural refrigerants;Lorentzen,1994
5. International Refrigeration Committee of the UK Institute of Refrigeration, 6th IIR Gustav Lorentzen natural working fluids conference at Glasgow, August 29–September 1, 2004.