APA (7th ed.) Citation

Seymour-Smith, M. (1976). Who's who in twentieth century literature. Weidenfeld.

Chicago Style (17th ed.) Citation

Seymour-Smith, Martin. Who's Who in Twentieth Century Literature. London: Weidenfeld, 1976.

MLA (9th ed.) Citation

Seymour-Smith, Martin. Who's Who in Twentieth Century Literature. Weidenfeld, 1976.