Não informado. (1969). Journal of Development Planning. United Nations, Department of Economic and Social Affairs.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNão informado. Journal of Development Planning. New York: United Nations, Department of Economic and Social Affairs, 1969.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিNão informado. Journal of Development Planning. United Nations, Department of Economic and Social Affairs, 1969.
সতর্কবাণী: সাইটেশন সবসময় 100% নির্ভুল হতে পারে না.