"Chart of San Joaquin River...Bethel Island, Frank's Tract, Andrus Island, Mokelumne River" (San Joaquin County, CA: Produced by Triumph Press, Inc.), 1972, Sub-Series 1.4, Box: 9, Folder: 4. Collection of California maps and guidebooks, SC-012. Pfau Library Special Collections. https://archivesspace.csusb.edu//repositories/3/archival_objects/6919 Accessed November 15, 2024.