Publisher
- National Atlas of the United States38
- Cartography Associates3
- Stanford Digital Repository3
- California. Division of Mines and Geology2
- County of Santa Cruz Information Services Department2
- Sacramento County GIS2
- California Geological Survey1
- County of San Mateo Information Services Department1
- Lew Rosenberg, Consulting Geologist1
- Solano County Department of Information Technology1
- Stanford University. Center for Spatial and Textual Analysis1