Headrick, D. R. (1981). The tools of empire: Technology and European imperialism in the nineteenth century. Oxford: Oxford University Press.
Chicago-tyylinen lähdeviittausHeadrick, Daniel R. The Tools of Empire: Technology and European Imperialism in the Nineteenth Century. Oxford: Oxford University Press, 1981.
MLA-viiteHeadrick, Daniel R. The Tools of Empire: Technology and European Imperialism in the Nineteenth Century. Oxford: Oxford University Press, 1981.
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