Shenton, J. P., & Meckler, A. M. (1973). Programmed learning aid for United States history. Learning Systems.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रShenton, James Patrick, और Alan M. Meckler. Programmed Learning Aid for United States History. Homewood, IL: Learning Systems, 1973.
एमएलए (9वां संस्करण) प्रशस्ति पत्रShenton, James Patrick, और Alan M. Meckler. Programmed Learning Aid for United States History. Learning Systems, 1973.
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