World Vision security manual : safety awareness for aid workers
MLA
Rogers, Charles, and Brian Sytsma. World Vision Security Manual: Safety Awareness for Aid Workers. Geneva, Switzerland: World Vision, 1999
APA, 7th edition
Rogers, C., & Sytsma, B. (1999). World Vision security manual: safety awareness for aid workers. Geneva, Switzerland: World Vision
Chicago, 17th edition
Rogers, Charles., and Brian Sytsma. World Vision security manual: safety awareness for aid workers. Geneva, Switzerland: World Vision, 1999