7M .E.Porter, The Competitive Advantage of Nations, N.Y. Free Press, 1990.p72.
8Graciela Chichilnisky. " Noah-South Trade and the Global Environment" , The Amen'can Economic Review, 1994,84,851-874.
9Michael J. Ferrantino., "International Trade, Environmental Quality and Public Policy" , The Word Economy, 1997,20,43-72.
10Diana Tussie. "The environment and international trade negotiations: open loops in the developing world" , The World Economy, Vol.22, No.4.1999, pp535-545.