Não informado. (1976). Water quality bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNão informado. Water Quality Bulletin. Ontario, Canada: World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিNão informado. Water Quality Bulletin. World Health Organization, Collaborating Centre on Surface and Ground Water, 1976.
সতর্কবাণী: সাইটেশন সবসময় 100% নির্ভুল হতে পারে না.