Author
Marshall, R. B. 1867-1949
Geological Survey (U.S.)
10
Illinois State Geological Survey
3
Brooks, Alfred H. 1871-1924
2
Darton, Nelson Horatio, 1865-1948
2
Kentucky Geological Survey
2
Smith, Philip S. 1877-1949
2
Atwood, Wallace Walter, 1872-1949
1
Bancroft, Howland, 1883-
1
Dale, T. Nelson 1845-1937
1
Fenneman, Nevin Melancthon, 1865-1945
1
Fuller, Myron L.
1
Geological Survey of Ohio
1
Gilpin, J. Elliott, 1866-1924
1
Girty, George Herbert, 1869-1939
1
Hayes, C. W. 1859-1916
1
Iowa
1
Irving, J. D. 1874-1918
1
Landes, Henry, 1867-1936
1
Loughlin, G. F. 1880-1946
1
Martin, G. C. 1875-1943
1
Minnesota. State Drainage Commission
1
Mississippi. Tallahatchie Drainage Commission
1
Munn, M. J. 1874-1949
1
Nickles, John M. 1859-1945
1
Ohio
1
Paige, Sidney, 1880-1968
1
Palmer, Chase, 1856-1927
1
Schaller, Waldemar T. 1882-1967
1
Shaw, E. W. 1881-1935
1
Smith, E. Eggleston, 1883-
1
Washington Geological Survey
1
Weed, Walter Harvey, 1862-1944
1
West Virginia Geological and Economic Survey
1
Woodruff, E. G. 1872-1952
1