APA (7 ম সংস্করণ) উদ্ধৃতি

Okun, D. A., & Ernst, W. R. (1987). Community piped water supply systems in developing countries: A planning manual. World Bank.

শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতি

Okun, Daniel Alexander, এবং Walter R. Ernst. Community Piped Water Supply Systems in Developing Countries: A Planning Manual. Washington, D.C: World Bank, 1987.

M.L.A (9 ম সংস্করণ) উদ্ধৃতি

Okun, Daniel Alexander, এবং Walter R. Ernst. Community Piped Water Supply Systems in Developing Countries: A Planning Manual. World Bank, 1987.