APA (7th ed.) Zitazioa
La Fay, H., Spiegel, t., Glanzman, L. S., & Christensen, A. E. The Vikings. National Geographic Society, Special Publications Division.
Chicago Style (17th ed.) Zitazioa
La Fay, Howard, ted Spiegel, Louis S. Glanzman, eta Arne Emil Christensen. The Vikings. Washington, EUA: National Geographic Society, Special Publications Division.
MLA (9th ed.) Zitazioa
La Fay, Howard, et al. The Vikings. National Geographic Society, Special Publications Division.
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