APA (7th ed.) Zitazioa
Alegre, H. (2017). Performance indicators for water supply services (Third edition.). IWA Publishing.
Chicago Style (17th ed.) Zitazioa
Alegre, Helena. Performance Indicators for Water Supply Services. Third edition. London, England: IWA Publishing, 2017.
MLA (9th ed.) Zitazioa
Alegre, Helena. Performance Indicators for Water Supply Services. Third edition. IWA Publishing, 2017.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.