Gillespie, S., & Mason, J. (1994). Controlling Vitamin A deficiency: A report based on the ACC/SCN Consultative Group Meeting on Strategies for the Control of Vitamin A Deficiency, 28-30 July 1993, Ottawa, Canada. World Health Organization.

Gillespie, Stuart, and John Mason. Controlling Vitamin A Deficiency: A Report Based on the ACC/SCN Consultative Group Meeting on Strategies for the Control of Vitamin A Deficiency, 28-30 July 1993, Ottawa, Canada. Geneva, Switzerland: World Health Organization, 1994.

Gillespie, Stuart, and John Mason. Controlling Vitamin A Deficiency: A Report Based on the ACC/SCN Consultative Group Meeting on Strategies for the Control of Vitamin A Deficiency, 28-30 July 1993, Ottawa, Canada. World Health Organization, 1994.