GRAY, A. S. The development of economic doctrine#An introductory survey#Alexander Gray. Longanns Northumberland Press.
Chicago-viite (17. p.)GRAY, Alexander Sir. The Development of Economic Doctrine#An Introductory Survey#Alexander Gray. Longanns Northumberland Press.
MLA-viite (8. p.)GRAY, Alexander Sir. The Development of Economic Doctrine#An Introductory Survey#Alexander Gray. Longanns Northumberland Press.
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