APA (7th ed.) Citation

Bretnor, R. (1980). The spear of Mars. Ace Books.

Chicago Style (17th ed.) Citation

Bretnor, Reginald. The Spear of Mars. New York: Ace Books, 1980.

MLA (9th ed.) Citation

Bretnor, Reginald. The Spear of Mars. Ace Books, 1980.

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