APA (7th ed.) Citation

Helfferich, K., & Gregory, T. E. G. (1969). Money. A. M. Kelley.

Chicago Style (17th ed.) Citation

Helfferich, Karl, and Theodor Emanuel Gugenheim Gregory. Money. New York: A. M. Kelley, 1969.

MLA (8th ed.) Citation

Helfferich, Karl, and Theodor Emanuel Gugenheim Gregory. Money. A. M. Kelley, 1969.