Card, O. S., & Brick, S. (2007). Pastwatch: The redemption of christopher columbus (Unabridged.). Blackstone Audio, Inc., and Buck 50 Productions, LLC.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रCard, Orson Scott, और Scott Brick. Pastwatch: The Redemption of Christopher Columbus. Unabridged. Ashland: Blackstone Audio, Inc., and Buck 50 Productions, LLC, 2007.
एमएलए (8वां संस्करण) प्रशस्ति पत्रCard, Orson Scott, और Scott Brick. Pastwatch: The Redemption of Christopher Columbus. Unabridged. Blackstone Audio, Inc., and Buck 50 Productions, LLC, 2007.
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