1. United Nations. Energy for a sustainable future: the secretary-general's advisory group on energy and climate change (AGECC) summary report and recommendations; 2010.
2. WA – World Atlas. http://www.worldatlas.com/aatlas/populations/ctypopls.htm.
3. The World Factbook, CIA; 2010.
4. Feasibility of a national programme on domestic biogas in Bangladesh;van Nes,2005
5. EIA, Energy Information Administration; 2010. http://www.eia.doe.gov/country/country_energy_data.cfm?fips=BG.