APA (7th ed.) Citation

Wells, H. G. (1899). When the sleeper wakes. Ace Books.

Chicago Style (17th ed.) Citation

Wells, H. G. When the Sleeper Wakes. New York: Ace Books, 1899.

MLA (9th ed.) Citation

Wells, H. G. When the Sleeper Wakes. Ace Books, 1899.