APA aipamena

Collier, P., Hoeffler, A., & Söderbom, M. (2001). On the Duration of Civil War. World Bank.

Chicago Style aipamena

Collier, P., A. Hoeffler, and M. Söderbom. On the Duration of Civil War. World Bank, 2001.

MLA aipamena

Collier, P., et al. On the Duration of Civil War. World Bank, 2001.