APA (7th ed.) Citation

Bova, B., & Lewis, T. (1997). Space travel. Writer's Digest Books.

Chicago Style (17th ed.) Citation

Bova, Ben, and Tony Lewis. Space Travel. Cincinnati: Writer's Digest Books, 1997.

MLA (9th ed.) Citation

Bova, Ben, and Tony Lewis. Space Travel. Writer's Digest Books, 1997.

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