Reconnoissance soil survey of northwest Texas
Carter, William T. (William Thomas), et al. Reconnoissance soil survey of northwest Texas, Book, 1922; digital images, (http://texashistory.unt.edu/ark:/67531/metapth19756 : accessed March 20, 2010), University of North Texas Libraries, The Portal to Texas History, http://texashistory.unt.edu; crediting UNT Libraries, Denton, Texas.