LEFTON ROBERT E. (2004). LEADERSHIP THROUGH PEOPLE SKILLS. MCGRAW-HILL.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रLEFTON ROBERT E. LEADERSHIP THROUGH PEOPLE SKILLS. NEW YORK: MCGRAW-HILL, 2004.
एमएलए (9वां संस्करण) प्रशस्ति पत्रLEFTON ROBERT E. LEADERSHIP THROUGH PEOPLE SKILLS. MCGRAW-HILL, 2004.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.