UNEP. (1979). Directory of institutions and individuals active in environmentally sound and appropriate technologies. Pergamon press.
শিকাগো স্টাইলে সাইটেশনUNEP. Directory of Institutions and Individuals Active in Environmentally Sound and Appropriate Technologies. NewYork: Pergamon press, 1979.
এমএলএ সাইটেশনUNEP. Directory of Institutions and Individuals Active in Environmentally Sound and Appropriate Technologies. Pergamon press, 1979.
সতর্কবাণী: সাইটেশন সবসময় 100% নির্ভুল হতে পারে না.