APA (7 वां संस्करण) प्रशस्ति पत्र

Holtz, H., & Zahn, D. (2004). How to succeed as an independent consultant (4th ed.). Wiley.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Holtz, Herman, और David Zahn. How to Succeed as an Independent Consultant. 4th ed. Hoboken, N.J.: Wiley, 2004.

एमएलए (8वां संस्करण) प्रशस्ति पत्र

Holtz, Herman, और David Zahn. How to Succeed as an Independent Consultant. 4th ed. Wiley, 2004.