1. Bailey, L.H. 1922. Pecan. In The Standard Cyclopedia of Horticulture, pp. 2513–2517. Vol. 5. New York: Macmillian.
2. Baskett, J.N. 1906. A study of route of Cabeza de Vaca. Texas State His. Assoc. Quart. 1(10):246–279.
3. Texas Dept. of Agric. Bull. No. 111;JH Burkett,1932
4. Celiz, F.F. 1935. In Diary of the Alarcon Expedition into Texas, 1718–1719. Trans. by Fritz Leo Hoffman, Quivira Soc. Pubis. 5:43–124.
5. USDA, Yearbook;HL Crane,1937