1. International Energy Agency,1995
2. Energy use in offices. Energy consumption guide, vol. 19 (ECG019). Energy efficiency best practice programme. UK Government, 2000.
3. DETR. Best practice programme—introduction to energy efficiency in buildings. UK Department of the Environment. Transport and the regions, 1994.
4. World population projection: 1994–95 edition;Bos,1994
5. Sustainable development and environment,2002