1. Coal bed methane primer: new source of natural gas-environmental implications;ALL Consulting, Montana Board of Oil and Gas Conservation,2004
2. The economics of Powder River Basin coalbed methane development;Bank,2006
3. Nitrogen removal from natural gas: phase II final report;Bomberger,1999
4. Investigation of preferential sorption behaviour of CO2 and CH4 on coals by high pressure adsorption/desorption experiments with gas mixtures;Busch,2003
5. Annual energy outlook 2007 with projections to 2030. US DOE, Energy Information Administration;EIA,2007