APA (7th ed.) Citation

(1966). Webster's third new international dictionary of: The english language unabridged. Encyclopaedia Britannica.

Chicago Style (17th ed.) Citation

Webster's Third New International Dictionary of: The English Language Unabridged. Chicago: Encyclopaedia Britannica, 1966.

MLA (9th ed.) Citation

Webster's Third New International Dictionary of: The English Language Unabridged. Encyclopaedia Britannica, 1966.