Vatsa, B. S., & Vatsa, S. (2009). Discrete mathematics (4th rev. ed.). New Age International.

Vatsa, B. S., and Suchi Vatsa. Discrete Mathematics. 4th rev. ed. New Delhi: New Age International, 2009.

Vatsa, B. S., and Suchi Vatsa. Discrete Mathematics. 4th rev. ed. New Age International, 2009.