Ross, P.R., Andrews, D.A., and Witkind, I.J., 1955, Geologic map of Montana: U.S. Geological Survey, 2 sheets, scale 1:500,000.
|Unit references|Stebinger, E., 1914, Titaniferous magnetite beds on the Blackfeet Indian Reservation, Montana: U.S. Geological Survey Bulletin 540, p. 329-337. Knechtel, M.M. and Patterson, S.H., 1956, Bentonite deposits in marine Cretaceous formations, Hardin district, Montana and Wyoming: U.S. Geological Survey Bulletin 1023, 116 p. Merewether, E.A., 1996, Stratigraphy and tectonic implications of Upper Cretaceous rocks in the Powder River basin, northeastern Wyoming and southeastern Montana, in Evolution of sedimentary basins--Powder River basin: U.S. Geological Survey Bul Knechtel, M.M. and Patterson, S.H., 1955, Bentonite deposits of the northern Black Hills district, Montana, Wyoming, and South Dakota: U.S. Geological Survey Miscellaneous Field Studies Map MF-36, 2 sheets, scale 1:48,000. [Also, U.S. Geologi Robinson, C.S., Mapel, W.J. and Bergendahl, M.H., 1964, Stratigraphy and structure of the northern and western flanks of the Black Hills uplift, Wyoming, Montana, and South Dakota: U.S. Geological Survey Professional Paper 404, 134 p.
Vuke, S.M., Wilde, E.M., Bergantino, R.N., Colton, R.B., 2001, Geologic map of the Alzada 30' x 60' quadrangle, eastern Montana: Montana Bureau of Mines and Geology Open File Report 433, scale 1:100,000.
Cobban, W.A., 1951, Colorado shale of central and northwestern Montana and equivalent rocks of the Black Hills: American Association of Petroleum Geologists Bulletin, v. 35, no. 10, p. 2170-2198.
Rubey, W.W., 1931, Lithologic studies of fine-grained Upper Cretaceous sedimentary rocks of the Black Hills region, IN Shorter contributions to general geology, 1930: U.S. Geological Survey Professional Paper 165-A, p. A1-A54. Knechtel, M.M. and Patterson, S.H., 1962, Bentonite deposits of the northern Black Hills district, Wyoming, Montana, and South Dakota, in Contributions to economic geology, 1958: U.S. Geological Survey Bulletin 1082-M, p. M893-M1030.