APA (7th ed.) Citation

Hughes, G. E., & Londey, D. G. (1965). The elements of formal logic. University Paperbacks.

Chicago Style (17th ed.) Citation

Hughes, G. E., and D. G. Londey. The Elements of Formal Logic. London: University Paperbacks, 1965.

MLA (8th ed.) Citation

Hughes, G. E., and D. G. Londey. The Elements of Formal Logic. University Paperbacks, 1965.