(1997). Vitamin A Supplements: A Guide to their Use in the Treatment and Prevention of Vitamin A Deficiency and Xerophthalmia (2nd.). World Health Organisation.
Chicago Stili AlıntıVitamin A Supplements: A Guide to Their Use in the Treatment and Prevention of Vitamin A Deficiency and Xerophthalmia. 2nd. Geneva: World Health Organisation, 1997.
MLA AlıntıVitamin A Supplements: A Guide to Their Use in the Treatment and Prevention of Vitamin A Deficiency and Xerophthalmia. 2nd. World Health Organisation, 1997.
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