Παραπομπή APA

Singh, J. W. (2009). Happiness: Gain and retain. Viva Books.

Παραπομπή Chicago Style

Singh, Just Win. Happiness: Gain and Retain. New Delhi: Viva Books, 2009.

Παραπομπή MLA

Singh, Just Win. Happiness: Gain and Retain. Viva Books, 2009.