Johnston, R. J. (1976). The World trade system: Some enquires into its spatial structure. G. Bell.
Chicago-viite (17. p.)Johnston, R. J. The World Trade System: Some Enquires into Its Spatial Structure. London: G. Bell, 1976.
MLA-viite (9. p.)Johnston, R. J. The World Trade System: Some Enquires into Its Spatial Structure. G. Bell, 1976.
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