Carl Koch. (1982). Communication skills for college students. National Book Store.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रCarl Koch. Communication Skills for College Students. Manila: National Book Store, 1982.
एमएलए (9वां संस्करण) प्रशस्ति पत्रCarl Koch. Communication Skills for College Students. National Book Store, 1982.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.