4Markusen,J.R and E.O.Swensson.Trade in Goods and Factor with International Differences in Technology.International Economic Review,1985,26(1):175-192.
5Melvin,James R.Trade in producer services:A Hecks-cher-Ohlin Approach.Journal of Political Economy,1989,97(5):1180-1196.
6Mundell,R.A.International Trade and Factor Mobility.American Economic Review,1957,47(3):321-335.