1. American Council for an Energy Efficient Economy (ACEEE), 2004. Online guide to energy-efficient commercial equipment. Retrieved on April 5, 2008 from 〈http://www.aceee.org/ogeece/ch1_index.htm〉.
2. Regularities in technological development: an environmental view;Ausubel,1989
3. The national building controls information program;Barwig,2002
4. Berkeley, California Municipal Code Section 19.72.090 required energy conservation measures for commercial buildings. Retrieved April 5, 2008 from 〈http://www.ci.berkeley.ca.us/bmc/berkeley_municipal_code/Title_19/72/090.html〉.
5. Bureau of Economic Analysis (BEA), US Department of Commerce, 2007. National Economic Accounts, Current and Real Gross Domestic Product, Retrieved January 1, 2008 from 〈http://www.bea.gov/national/index.htm#gdp〉.