Havil, J. (2008). Impossible?: Surprising solutions to counterintuitive conundrums. Princeton University Press.
Čikaški stil citiranja (17. izdanje)Havil, Julian. Impossible?: Surprising Solutions to Counterintuitive Conundrums. Princeton, N.J: Princeton University Press, 2008.
MLA način citiranja (9. izdanje)Havil, Julian. Impossible?: Surprising Solutions to Counterintuitive Conundrums. Princeton University Press, 2008.
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