World Health Organization. (1991). Environmental health criteria 148. World Health Organization.
Chicago-viite (17. p.)World Health Organization. Environmental Health Criteria 148. Geneva: World Health Organization, 1991.
MLA-viite (8. p.)World Health Organization. Environmental Health Criteria 148. World Health Organization, 1991.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.