1. United States Environmental Protection Agency EPA's Position on the Energy Crisis http://www.epa.gov/history/topics/energy/01.html 2012
2. Advances in fermentative biohydrogen production: The way forward?;Hallenbeck;Trends Biotechnol,2009
3. Markets and Markets Hydrogen generation market- by merchant & captive type, distributed & centralized generation, application & technology- trends & global forecasts (2011-2016) http://articles.pubarticles.com/hydrogen-generation-market-by-merchant-captive-type-distributed-centralized-1323076864,561523.html 2011
4. An evaluative report and challenges for fermentative biohydrogen production;Sinha;Int J Hydrogen Energ,2011
5. The Prospect of purple non-sulfur (PNS) photosynthetic bacteria for hydrogen production: The present state of the art;Basak;World J Microb Biot,2007