World Health Organization. (1993). Guidelines for drinking - water quality: Recommendations. World Health Organization.
Chicago Style aipamenaWorld Health Organization. Guidelines for Drinking - Water Quality: Recommendations. Geneva: World Health Organization, 1993.
MLA aipamenaWorld Health Organization. Guidelines for Drinking - Water Quality: Recommendations. World Health Organization, 1993.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.