APA (7th ed.) Citation

Watson, S. J. (2012). Before I go to sleep (1. publ.). Black Swan.

Chicago Style (17th ed.) Citation

Watson, S. J. Before I Go to Sleep. 1. publ. London: Black Swan, 2012.

MLA (9th ed.) Citation

Watson, S. J. Before I Go to Sleep. 1. publ. Black Swan, 2012.

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