APA (7 वां संस्करण) प्रशस्ति पत्र

Halm, G. N. (1968). Economic systems: A comparative analysis (3rd ed.). Holt, Rinehart and Winston.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Halm, George Nikolaus. Economic Systems: A Comparative Analysis. 3rd ed. New York: Holt, Rinehart and Winston, 1968.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Halm, George Nikolaus. Economic Systems: A Comparative Analysis. 3rd ed. Holt, Rinehart and Winston, 1968.