APA (7th ed.) Citation

Gregory, S. (2009). The Westminster poisoner. Sphere.

Chicago Style (17th ed.) Citation

Gregory, Susanna. The Westminster Poisoner. london: Sphere, 2009.

MLA (8th ed.) Citation

Gregory, Susanna. The Westminster Poisoner. Sphere, 2009.

Warning: These citations may not always be 100% accurate.