APA (7th ed.) Citation

Christensen, Wagner, & Halliday. (2001). Psychology. Viva Books Private Limited.

Chicago Style (17th ed.) Citation

Christensen, Wagner, and Halliday. Psychology. New Delhi: Viva Books Private Limited, 2001.

MLA (8th ed.) Citation

Christensen, et al. Psychology. Viva Books Private Limited, 2001.