APA (7th ed.) Citation

Blackham, H. J. (1989). Six existentialist thinkers. Routledge.

Chicago Style (17th ed.) Citation

Blackham, H. J. Six Existentialist Thinkers. London: Routledge, 1989.

MLA (9th ed.) Citation

Blackham, H. J. Six Existentialist Thinkers. Routledge, 1989.