North of the Border. Texas Academy of Science Proceedings and Transactions 25 (1941): 77-85.

North of the Border. Texas Academy of Science Proceedings and Transactions 25 (1941): 77-85., Box: 66, Folder: 4. George I. Sánchez Papers, 23866736. Benson Latin American Collection, The University of Texas at Austin. https://archives.lib.utexas.edu/repositories/4/archival_objects/541250 Accessed September 26, 2026.