APA (7th ed.) Citation

Harmon, D. E. (2018). The early days of space exploration. Britannica Educational Publishing in association with Rosen Educational Services.

Chicago Style (17th ed.) Citation

Harmon, Daniel E. The Early Days of Space Exploration. New York, NY: Britannica Educational Publishing in association with Rosen Educational Services, 2018.

MLA (8th ed.) Citation

Harmon, Daniel E. The Early Days of Space Exploration. Britannica Educational Publishing in association with Rosen Educational Services, 2018.

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