Blackburn's Map of County California (Produced by O.V. Blackburn [Quantity 2]), 1932, Sub-Series 1.5, Box: 24, Folder: 2. Collection of California maps and guidebooks, SC-012. Pfau Library Special Collections. https://archivesspace.csusb.edu//repositories/3/archival_objects/15330 Accessed January 09, 2026.