HILLIER, F. S., & LIEBERMAN, G. J. (1990). Introduction to operations research.-- ed. 5. McGraw-Hill.

HILLIER, Frederick S., and Gerald J. LIEBERMAN. Introduction to Operations Research.-- Ed. 5. New York: McGraw-Hill, 1990.

HILLIER, Frederick S., and Gerald J. LIEBERMAN. Introduction to Operations Research.-- Ed. 5. McGraw-Hill, 1990.