Não informado. (1976). Water quality bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water.
Chicago-Zitierstil (17. Ausg.)Não informado. Water Quality Bulletin. Ontario, Canada: World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
MLA-Zitierstil (8. Ausg.)Não informado. Water Quality Bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.