Mark Twain (2011). “A Connecticut Yankee in King Arthur's CourtUn yanqui en la corte del Rey Arturo: English-Spanish Parallel Text Edition Volume One”, p.220, Lulu.com
George Catlin (1857). “Illustrations of the Manners, Customs, and Condition of the North American Indians: With Letters and Notes Written During Eight Years of Travel and Adventure Among the Wildest and Most Remarkable Tribes Now Existing ; with 360 Engravings, from the Author's Original Paintings”, p.16