6Cohen, Benjamin J, The Future of Sterling as an International Currency, London: Macmillan, 1971.
7Mundell R. A. , The International Economics : Past, Present and Future, London: Macmillan, 2003.
8McKinnon R. L. , "Optimum Currency Areas," American Economic Review, vol. 53, no. 3, 1963,pp. 457 - 477.
9Kenen P, B. , The Theory of Optimum Currency Areas :An Eclectic View, in Funerary Problems of the International Economy, Chicago :University of Chicago Press, 1969.
10James C Ingrain, Comment : The Currency Area Problem, in Monetary Problems of the International Economy, edited by Robert A. Mun- dell and Alexander, Swoboda, Chicago: University of Chicano Press, 1969.