APA-viite (7. p.)
Tortell, P. (2020). Earth 2020: An insider's guide to a rapidly changing planet. Open Book Publishers.
Chicago-viite (17. p.)
Tortell, Philippe. Earth 2020: An Insider's Guide to a Rapidly Changing Planet. Cambridge, England: Open Book Publishers, 2020.
MLA-viite (9. p.)
Tortell, Philippe. Earth 2020: An Insider's Guide to a Rapidly Changing Planet. Open Book Publishers, 2020.
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