APA (7th ed.) Citation

Smith, H. L. (1942). Airways: The history of commercial aviation in the United States. A.A. Knopf.

Chicago Style (17th ed.) Citation

Smith, Henry Ladd. Airways: The History of Commercial Aviation in the United States. New York: A.A. Knopf, 1942.

MLA (9th ed.) Citation

Smith, Henry Ladd. Airways: The History of Commercial Aviation in the United States. A.A. Knopf, 1942.