Sommer, A. (1995). Vitamin A deficiency and its consequences: A field guide to detection and control (3rd ed.). World Health Organization.
Chicago-viite (17. p.)Sommer, Alfred. Vitamin A Deficiency and Its Consequences: A Field Guide to Detection and Control. 3rd ed. Geneva: World Health Organization, 1995.
MLA-viite (8. p.)Sommer, Alfred. Vitamin A Deficiency and Its Consequences: A Field Guide to Detection and Control. 3rd ed. World Health Organization, 1995.
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