Petrified Forest National Park, Chap. 38, in Harris, A.G., and Tuttle, Esther, Geology of national parks (3rd ed.)

Tuttle, S.D., 1983, Petrified Forest National Park, Chap. 38, in Harris, A.G., and Tuttle, Esther, Geology of national parks (3rd ed.): Dubuque, Iowa, Kendall/Hunt Publishing Co., p. 463-473.