"The Learning Curve in Modern Languages,", 192-

"The Learning Curve in Modern Languages,", 192-, Box: 49, Folder: 3. Carlos E. Castañeda Papers, 23587615. Benson Latin American Collection, The University of Texas at Austin. https://archives.lib.utexas.edu/repositories/4/archival_objects/357700 Accessed September 25, 2026.