Não informado. (1978). World Health Statistics Quarterly. World Health Organization.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. World Health Statistics Quarterly. Geneva, Suíça: World Health Organization, 1978.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. World Health Statistics Quarterly. World Health Organization, 1978.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.