APA (7th ed.) Citation

Kaufman, A. A., & Hansen, R. O. (2008). Principles of the gravitational method. Elsevier.

Chicago Style (17th ed.) Citation

Kaufman, Alexander A., and R. O. Hansen. Principles of the Gravitational Method. Amsterdam ; London: Elsevier, 2008.

MLA (9th ed.) Citation

Kaufman, Alexander A., and R. O. Hansen. Principles of the Gravitational Method. Elsevier, 2008.