Não informado. (1969). Environmental Health. Environmental Health Officers Association.
Chicago-viite (17. p.)Não informado. Environmental Health. London: Environmental Health Officers Association, 1969.
MLA-viite (8. p.)Não informado. Environmental Health. Environmental Health Officers Association, 1969.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.