Gray ,N.F. (2008). Drinking Water Quality (2.). Cambridge University Press.
Chicago Style aipamenaGray ,N.F. Drinking Water Quality. 2. Delhi: Cambridge University Press, 2008.
MLA aipamenaGray ,N.F. Drinking Water Quality. 2. Cambridge University Press, 2008.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.