Questar, Inc. (2008). Treasures of America's national parks. Disstributed by Questar.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रQuestar, Inc. Treasures of America's National Parks. Chicago, IL: Disstributed by Questar, 2008.
एमएलए (8वां संस्करण) प्रशस्ति पत्रQuestar, Inc. Treasures of America's National Parks. Disstributed by Questar, 2008.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.