WGBH (Television station : Boston, Mass.). Science Unit, British Broadcasting Corporation. Television Service, & WGBH Video (Firm). (2006). Secrets of lost empires. WGBH Boston Video.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWGBH (Television station : Boston, Mass.). Science Unit, British Broadcasting Corporation. Television Service, और WGBH Video (Firm). Secrets of Lost Empires. [Boston, MA]: WGBH Boston Video, 2006.
एमएलए (8वां संस्करण) प्रशस्ति पत्रWGBH (Television station : Boston, Mass.). Science Unit, et al. Secrets of Lost Empires. WGBH Boston Video, 2006.
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