APA (7th ed.) Zitazioa
Velm, G. (2013). Wiley AP U.S. history. John Wiley and Sons.
Chicago Style (17th ed.) Zitazioa
Velm, Greg. Wiley AP U.S. History. Indianapolis, Ind.: John Wiley and Sons, 2013.
MLA (9th ed.) Zitazioa
Velm, Greg. Wiley AP U.S. History. John Wiley and Sons, 2013.
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