APA (7th ed.) Citation

Martel, C., Perley, C. W., MacNair, M. W., & Schmidt, A. F. W. (1916). Classification. Class D: Universal and old world history. U. S. Government Printing Office.

Chicago Style (17th ed.) Citation

Martel, Charles, Clarence Warner Perley, Mary Wilson MacNair, and A. F. W. Schmidt. Classification. Class D: Universal and Old World History. Washington: U. S. Government Printing Office, 1916.

MLA (9th ed.) Citation

Martel, Charles, et al. Classification. Class D: Universal and Old World History. U. S. Government Printing Office, 1916.