Whitten, J. L., Bentley, L. D., & Dittman, K. C. (1998). Systems analysis and design methods (4th ed.). Irwin/McGraw-Hill ; Galgotia.

Whitten, Jeffrey L., Lonnie D. Bentley, and Kevin C. Dittman. Systems Analysis and Design Methods. 4th ed. Boston, Mass. : New Delhi: Irwin/McGraw-Hill ; Galgotia, 1998.

Whitten, Jeffrey L., et al. Systems Analysis and Design Methods. 4th ed. Irwin/McGraw-Hill ; Galgotia, 1998.