Oil and gas fields of Colorado: Statistical data through 1981. 72 pages. 3 figures. See also IS-50. Digital PDF download. IS-18D
Information Series 18 is presented as an update and revision of a previous CGS publication, IS-03. Accompanying IS-18, the CGS also published MS-22, Colorado Oil and Gas Fields: this publication was superseded by IS-50 Oil and Gas Fields of Colorado Statistical Summary through 1996.