Não informado. (1970). Environmental quality. Council on Environmental Quality, Executive Office of the President.
Chicago-referens (17:e uppl.)Não informado. Environmental Quality. Washington: Council on Environmental Quality, Executive Office of the President, 1970.
MLA-referens (8:e uppl.)Não informado. Environmental Quality. Council on Environmental Quality, Executive Office of the President, 1970.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.