Shelley, Lewis Orman.
1932. Inbreeding downy woodpeckers. Bird-Banding, vol. 3, pp. 69-70.
1933. Some notes on the hairy woodpecker. Bird-Banding, vol. 4, pp. 204-205.
Sherman, Althea Rosina.
1910. At the sign of the northern flicker. Wilson Bull., vol. 22, pp. 135-171.
Sherwood, William E.
1927. Feeding habits of Lewis woodpecker. Condor, vol. 29, p. 171.
Simmons, George Finlay.
1915. On the nesting of certain birds in Texas. Auk, vol. 32, pp. 317-331.
1925. Birds of the Austin region.