UNEP. (1979). Directory of institutions and individuals active in environmentally sound and appropriate technologies. Pergamon press.
استشهاد بنمط شيكاغوUNEP. Directory of Institutions and Individuals Active in Environmentally Sound and Appropriate Technologies. NewYork: Pergamon press, 1979.
MLA استشهادUNEP. Directory of Institutions and Individuals Active in Environmentally Sound and Appropriate Technologies. Pergamon press, 1979.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.