APA-viite (7. p.)
Richards, J. F. (2003). The unending frontier: An environmental history of the early modern world by. University of California Press.
Chicago-viite (17. p.)
Richards, John F. The Unending Frontier: An Environmental History of the Early Modern World by. Berkeley: University of California Press, 2003.
MLA-viite (9. p.)
Richards, John F. The Unending Frontier: An Environmental History of the Early Modern World by. University of California Press, 2003.
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