- Gap Analysis Program (U.S.)60
- International Association of Seismology and Physics of the Earth's Interior31
- International Heat Flow Commission31
- Oklahoma State University. Department of Geography. Cartography Service31
- Geological Survey (U.S.)13
- Environmental Systems Research Institute (Redlands, Calif.)11
- California. Department of Water Resources9
- Arndt, Raymond E.8
- Bawiec, Walter J.8
- Beikman, Helen M.8
- King, Philip B.8
- Nature Conservancy (U.S.)8
- Schruben, Paul G.8
- DTIS7
- Golden, Nadine E.7
- Pacific Coastal and Marine Science Center7
- California. Department of Fish and Game. Marine Resources Region6
- Dartnell, Peter6
- Department of Conservation & Development, Contra Costa County6
- Kvitek, Rikk G.6
