APA (7th ed.) Citation

Levy, D. H., & O'Byrne, J. (1994). Skywatching. Harper Collins Publishers.

Chicago Style (17th ed.) Citation

Levy, David H., and John O'Byrne. Skywatching. London: Harper Collins Publishers, 1994.

MLA (8th ed.) Citation

Levy, David H., and John O'Byrne. Skywatching. Harper Collins Publishers, 1994.