APA (7 वां संस्करण) प्रशस्ति पत्र

Ruppenthal, K. M. (1963). Perspectives in transportation. Graduate School of Business.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Ruppenthal, Karl Maxwell. Perspectives in Transportation. Stanford, Calif: Graduate School of Business, 1963.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Ruppenthal, Karl Maxwell. Perspectives in Transportation. Graduate School of Business, 1963.