"Review of 1966 Petroleum Developments in South America, Central America, and Caribbean Area" W.H. Hadley and C.H. Neff, AAPG Bulletin, V. 51/8, August 1967, Box: 10, Folder: 38. Hollis Hedberg papers, RH MS 546. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/149260 Accessed May 18, 2024.