Writing Improvement Project. (1977). Building English skills. McDougal, Littell & Company.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWriting Improvement Project. Building English Skills. Evanston, Illinois: McDougal, Littell & Company, 1977.
एमएलए (9वां संस्करण) प्रशस्ति पत्रWriting Improvement Project. Building English Skills. McDougal, Littell & Company, 1977.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.