APA (7th ed.) Citation

(1981). Encyclopaedia Britannica: Micropaedia (ready reference and index) (15th ed.). Encyclopaedia Britannica Inc.

Chicago Style (17th ed.) Citation

Encyclopaedia Britannica: Micropaedia (ready Reference and Index). 15th ed. London: Encyclopaedia Britannica Inc, 1981.

MLA (8th ed.) Citation

Encyclopaedia Britannica: Micropaedia (ready Reference and Index). 15th ed. Encyclopaedia Britannica Inc, 1981.

Warning: These citations may not always be 100% accurate.