Não informado. (1969). Environmental Health. Environmental Health Officers Association.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Environmental Health. London: Environmental Health Officers Association, 1969.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Environmental Health. Environmental Health Officers Association, 1969.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.