Cita APA (7th ed.)
Tortell, P. (2020). Earth 2020: An insider's guide to a rapidly changing planet. Open Book Publishers.
Cita Chicago (17th ed.)
Tortell, Philippe. Earth 2020: An Insider's Guide to a Rapidly Changing Planet. Cambridge, England: Open Book Publishers, 2020.
Cita MLA (9th ed.)
Tortell, Philippe. Earth 2020: An Insider's Guide to a Rapidly Changing Planet. Open Book Publishers, 2020.
Atenció: Aquestes cites poden no estar 100% correctes.