APA (7th ed.) Citation

(1958). The encyclopedia Americana: The international reference work : complete in thirty volumes. Americana Corporation.

Chicago Style (17th ed.) Citation

The Encyclopedia Americana: The International Reference Work : Complete in Thirty Volumes. New York, [etc]: Americana Corporation, 1958.

MLA (9th ed.) Citation

The Encyclopedia Americana: The International Reference Work : Complete in Thirty Volumes. Americana Corporation, 1958.