APA (7th ed.) Citation

Bull, G. M., & Packham, S. F. (1971). Time-sharing systems. McGraw-Hill.

Chicago Style (17th ed.) Citation

Bull, G. M., and S. F. Packham. Time-sharing Systems. New York: McGraw-Hill, 1971.

MLA (8th ed.) Citation

Bull, G. M., and S. F. Packham. Time-sharing Systems. McGraw-Hill, 1971.