APA (7th ed.) Zitazioa
Wilson, R. J., & Stewart, I. Four Colors Suffice: How the Map Problem Was Solved (Nueva ed.). Princeton University.
Chicago Style (17th ed.) Zitazioa
Wilson, Robin J., eta Ian Stewart. Four Colors Suffice: How the Map Problem Was Solved. Nueva ed. Princeton, EUA: Princeton University.
MLA (9th ed.) Zitazioa
Wilson, Robin J., eta Ian Stewart. Four Colors Suffice: How the Map Problem Was Solved. Nueva ed. Princeton University.
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