APA (7th ed.) Citation

Hughes, G. E., & Cresswell, M. J. (1996). A new introduction to modal logic. Routledge.

Chicago Style (17th ed.) Citation

Hughes, G. E., and M. J. Cresswell. A New Introduction to Modal Logic. London: Routledge, 1996.

MLA (9th ed.) Citation

Hughes, G. E., and M. J. Cresswell. A New Introduction to Modal Logic. Routledge, 1996.