United States Department of the Interior, Geological Survey, Oil and Gas Potential of the Designated Areas in the Gulf of Mexico and Offshore Southern California, Administrative Report, January 16, 1981, Box: 25, Folder: 6. Hollis Hedberg papers, RH MS 546. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/149621 Accessed April 26, 2024.