APA (7th ed.) Zitazioa
Clarke, A. C. The Challenge of the Spaceship. Ballantine Books.
Chicago Style (17th ed.) Zitazioa
Clarke, Arthur C. The Challenge of the Spaceship. Nueva York, EUA: Ballantine Books.
MLA (9th ed.) Zitazioa
Clarke, Arthur C. The Challenge of the Spaceship. Ballantine Books.
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