Cita APA (7th ed.)
Wells, W. (2009). Apocalypse When?: Calculating How Long the Human Race Will Survive. Praxis. https://doi.org/10.1007/978-0-387-09837-1
Cita Chicago (17th ed.)
Wells, Willard. Apocalypse When?: Calculating How Long the Human Race Will Survive. New York, NY: Praxis, 2009. https://doi.org/10.1007/978-0-387-09837-1.
Cita MLA (9th ed.)
Wells, Willard. Apocalypse When?: Calculating How Long the Human Race Will Survive. Praxis, 2009. https://doi.org/10.1007/978-0-387-09837-1.
Atenció: Aquestes cites poden no estar 100% correctes.