APA (7th ed.) Citation

Glenn, J. H. 1. Letters to John Glenn. World Book Encyclopedia Science Service, 1964.

Chicago Style (17th ed.) Citation

Glenn, John Herschel 1921. Letters to John Glenn. Houston, Tex: World Book Encyclopedia Science Service, 1964.

MLA (9th ed.) Citation

Glenn, John Herschel 1921. Letters to John Glenn. World Book Encyclopedia Science Service, 1964.

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