Não informado. (1969). WHO library acquisitions. World Health Organization.
Chicago-Zitierstil (17. Ausg.)Não informado. WHO Library Acquisitions. Geneva, Suíça: World Health Organization, 1969.
MLA-Zitierstil (8. Ausg.)Não informado. WHO Library Acquisitions. World Health Organization, 1969.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.