5Balassa, B. ( 1989 ) : Comparative Advantage, Trade and Economic Development, New York University Press.
6Grubel, G. and P. Lloyd ( 1975) : Intra-industry Trade: The Theory and Measurement of International Trade in Differentiated Products, London: MacMillan.
7Greenaway, David, R. C. Hine and C. Milner (1994):"Country-specified Factors and the Pattern of Horizontal and Vertical Trade in the UK", Weltwirtschaftliches Archly 130(1),pp. 77-100.
