Schuchert, Charles, 1918, The Cambrian of the Grand Canyon of Arizona: American Journal of Science, 4th ser., v. 45, p. 362-369.
American Journal of Science, 4th ser., v. 45, p. 362-369.
Stratigraphy, Tapeats Sandstone - Tonto Group - Cambrian, Bright Angel Shale, Muav Limestone,