1. Strategic Research Institute. Coalbed and coal mine methane: a new energy resource for 21st century. 2000, www.srinstitute.com.
2. Nelson CR. Gas Research Institute North American Coalbed Methane Resource Map. GRI Report No. GRI-99/0131, 1999.
3. Hill DG, Nelson CR, Brandenburg CF. Changing perceptions regarding the size and production potential of north America coalbed methane resources. 2000, www.srinstitute.com.
4. Exploring uses for coalbed methane product water;Reddy;Reflections (College of Agriculture, University of Wyoming, Laramie, WY),2001
5. Ellis MS, Stricker GD, Flores RM, Bader LR. Sulfur and ash in Paleocene Wyodak-Anderson coal in the Powder River Basin, Wyoming and Montana: a non-sequitur to externalities beyond 2000. Proceedings of the 23rd International Technical Conference on Coal Utilization, Clearwater, FL, 1998.