APA
World Health Organization. Expanded Programme on Immunization, World Health Organization. Nutrition Unit, . (1993). How to give vitamin A supplements : a guide for health workers. Geneva: World Health Organization.
Chicago
World Health Organization. Expanded Programme on Immunization, World Health Organization. Nutrition Unit, . 1993. How to give vitamin A supplements : a guide for health workers. Geneva: World Health Organization.
Harvard
World Health Organization. Expanded Programme on Immunization, World Health Organization. Nutrition Unit, . (1993). How to give vitamin A supplements : a guide for health workers. Geneva: World Health Organization.
MLA
World Health Organization. Expanded Programme on Immunization, World Health Organization. Nutrition Unit, . How to give vitamin A supplements : a guide for health workers. Geneva: World Health Organization. 1993.