Norman Bridwell. (1997). Clifford's Spring Clean-Up (Clifford the Big Red Dog) (21st Printing.). Cartwheel.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNorman Bridwell. Clifford's Spring Clean-Up (Clifford the Big Red Dog). 21st Printing. Cartwheel, 1997.
एमएलए (9वां संस्करण) प्रशस्ति पत्रNorman Bridwell. Clifford's Spring Clean-Up (Clifford the Big Red Dog). 21st Printing. Cartwheel, 1997.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.