1. AGA, 1983, “Survey of Underground Gas Storage Facilities in the United States and Canada.” Operating Section Report, American Gas Association, Statistics Task Group, Arlington, VA.
2. AGA, 1986, “Gas Facts 1985, A Statistical Record of the Gas Utility Industry, American Gas Association,” Department of Statistics, Arlington, VA.
3. AGA, 1987, “Gas Facts 1986, A Statistical Record of the Gas Utility Industry, American Gas Association,” Department of Statistics, Arlington, VA.
4. ERT, 1987, “Oil and Gas Industry Exploration and Production Wastes.” Prepared for the American Petroleum Institute. July.
5. Environmental Reporter, 1991, Volume 21, 1989, Bureau of National Affairs, Inc., Washington, D.C. March 8.