"Santa Ana, San Joaquin, Guario, and Santa Rosa Oil Fields (Anaco Fields), Central Anzoatequi, Venezuela" by H.J. Funkhouser, L.C. Sass, and H.D. Hedberg, Box: 11, Folder: 11. Hollis Hedberg papers, RH MS 546. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/149273 Accessed May 03, 2024.