E & G Energy Inc. / Western Energy Co. / Chevron U.S.A. / B. D. Resources Inc. / Kindred Petroleum Co. / Northridge Western Energy Co. / Texaco / Reliance Energy Inc. / Enron Oil & Gas Company / Burlington Resources / Penwell Energy Inc. / Twin Montana Inc. / Avra Oil Company / Production Co. / Southwest Royalties Inc. / Lario Oil & Gas Company / BC Operating Inc. / Chalfant Properties Inc. / Enserch Exploration Inc. / Oilfield Management Inc. / Perry & Perry Inc. / Marathon Oil Company / Apache Corp. / Sonat Exploration Company / Xeric Oil & Gas Corp. / UMC Petroleum Corporation / IP Petroleum Company Inc. / Greenhill Petroleum Corp. / /