1. E.W. Brown, An Introduction to Solar Energy. http://www.ccs.neu.edu/home/feneric/solar.html.
2. Solar Energy. A Reference Guide for Users John Maina and Peter Gichohi. http://my.ewb-usa.org/theme/library/myewb-usa/project-resources/technical/solarenergyareferenceguide.pdf.
3. http://www.sandia.gov/∼jytsao/Solar%20FAQs.pdf.
4. Basic Needs in Solar Energy Utilisation Report (BES 2005). http://science.energy.gov/∼/media/bes/pdf/reports/files/seu_rpt.pdf.