"Cultural Dynamics and Evolutionary Theory," in Social Change in Developing Areas: A Reinterpretation of Evolutionary Theory, eds. Herbert R. Barringer, George I. Blanksten, and Raymond W. Mack. Cambridge, Mass.: Schenkman Publishing Company, Inc., pp.68-96. Also published in Spanish edition, entitled Cambios Sociales en Legiones en Desarrollo. Mexico, D.F.: Editorial Roble, pp.79-110., 1965, 1968, Box: 122, Folder: 10. Morris Edward Opler papers, 14-25-3238. Division of Rare and Manuscript Collections. https://archives.library.cornell.edu/repositories/2/archival_objects/240605 Accessed April 15, 2026.