W. L. Stokes
Stokes, W. L. 1954 Pterodactyl tracks from the Morrison Formation near Carrizo Mountains, Arizona. Bull. geol. Soc. Am. 65, 1309.
Stokes, W. L. 1957 Pterodactyl tracks from the Morrison Formation. J. Paleont. 31, 952–954.
Stokes, W. L. & Madsen, J. H. 1979 Environmental significance of pterosaur tracks in the Navajo Sandstone (Jurassic) Grand County, Utah. Brigham Young Univ. Geol. Stud. 26, 21–26.