[1]. Siegel, D.S., (2009).» Green Management Matters Only If It Yields More Green»: An Economic/ Strategic Perspective, The Academy of Management Perspectives Archive, Academy of Management. Vol. 26, p.p (5-12).
[2] . Petsonk, C. A. (1989). «Role of the United Nations Environment Program UNEP) in the Development of International Environmental Law Recent Developments in International Organizations , American University Journal of International Law and Policy Vol . 39, Pages.351.
[3].M.Hardy (1973)» United Nations Environment Program», Natural Resources Journal Vol. 13 , P.235.