1. Status of solar wind renewable energy in India
2. Andreas Bauer;Jackson;Theresa Magorian Friedlmeier, and Michael Powalla,2015
3. Panasonic;Release;Hit Solar Cell Achieves World’s Highest Energy Conversion Effciency of,2014
4. http://www.webelements.com/periodicity/abundance crust.
5. Hironori Katagiri, Masato Nishimura, Takeshi Onozawa, Shinichi Maruyama Masato Fujita, Toshiyuki Sega and Taku Watanabe, Proceedings of the Power Conversion Conference - Nagaoka 1997, Volume: 2.