Grover, Nathan Clifford (1868-1956) Parker, Glenn Lane (1884-1946) Lamb, William Alfred (1881- ) United States of America. Geological Survey.
Grover, Nathan Clifford (1868-1956) Lamb, William Alfred (1881- ) Soulé, S. B. Spiegel, Jacob Birk Grosbach, H. E. Beckman, Henry Claus (1888- ) United States of America. Geological Survey.
Grover, Nathan Clifford (1868-1956) Lamb, William Alfred (1881- ) Paulsen, Carl G. Follansbee, Robert (1879-1952) Spiegel, Jacob Birk Kinnison, Harvey Banks (1890- ) Beckman, Henry Claus (1888- ) United States of America. Geological Survey.