- Geological Survey (U.S.)4
- Hatch, Norman L.2
- Pomeroy, John S., 1929-2
- L.J. Richards & Co., cartographer, publisher1
- Leo, Gerhard W.1
- Osberg, Philip H. (Philip Henry)1
- Peper, John D.1
- Stanley, Rolfe S.1
- Willard, Max Emory, 1914-1
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