APA (7 वां संस्करण) प्रशस्ति पत्र

Hartman, R., & Gustafson, E. (1966). Workbook for the foundations of modern economics series. Prentice-Hall.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Hartman, Robert, और Eric Gustafson. Workbook for the Foundations of Modern Economics Series. Englewood Cliffs, N.J: Prentice-Hall, 1966.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Hartman, Robert, और Eric Gustafson. Workbook for the Foundations of Modern Economics Series. Prentice-Hall, 1966.