"Mountain, Lake, Desert and River Playgrounds San Bernardino County" (San Bernardino, CA: Produced by San Bernardino County Board of Trade), undated, Sub-Series 2.4, Box: 25, Folder: 4. Collection of California maps and guidebooks, SC-012. Pfau Library Special Collections. https://archivesspace.csusb.edu//repositories/3/archival_objects/15452 Accessed January 10, 2026.