Levin, R. I., & Kirkpatrick, C. A. (1971). Quantitative approaches to management (2d ed.). McGraw-Hill.

Levin, Richard I., and Charles A. Kirkpatrick. Quantitative Approaches to Management. 2d ed. New York: McGraw-Hill, 1971.

Levin, Richard I., and Charles A. Kirkpatrick. Quantitative Approaches to Management. 2d ed. McGraw-Hill, 1971.