"Calexico/Mexico Gateway to Mexico" (Calexico, CA; Produced by The Calexico Chamber of Commerce), 1975, Sub-Series 1.1, Box: 21, Folder: 3. Collection of California maps and guidebooks, SC-012. Pfau Library Special Collections. https://archivesspace.csusb.edu//repositories/3/archival_objects/10403 Accessed November 15, 2024.