Aerial Radiometric and Magnetic Reconnaissance Survey of Portions of Arizona, Idaho, Montana, New Mexico, South Dakota and Washington: Final Report, Volume 2-D. Choteau Quadrangle, report, May 1979; (https://digital.library.unt.edu/ark:/67531/metadc784498/m1/1/: accessed April 17, 2024), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .