APA (7th ed.) Citation

Villiers, T., & Wilken, S. (1998). Waiver, variation, and estoppel. J. Wiley.

Chicago Style (17th ed.) Citation

Villiers, Theresa, and Sean Wilken. Waiver, Variation, and Estoppel. New York: J. Wiley, 1998.

MLA (9th ed.) Citation

Villiers, Theresa, and Sean Wilken. Waiver, Variation, and Estoppel. J. Wiley, 1998.