APA (7th ed.) Citation

Readers Digest Asso. (1980). Natural wonders of the world. RDA.

Chicago Style (17th ed.) Citation

Readers Digest Asso. Natural Wonders of the World. New York: RDA, 1980.

MLA (9th ed.) Citation

Readers Digest Asso. Natural Wonders of the World. RDA, 1980.

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