Worthen, B. R., & Sanders, J. R. (1987). Educational evaluation: Alternative approaches and practical guidelines. Longman.

Worthen, Blaine R., and James R. Sanders. Educational Evaluation: Alternative Approaches and Practical Guidelines. New York: Longman, 1987.

Worthen, Blaine R., and James R. Sanders. Educational Evaluation: Alternative Approaches and Practical Guidelines. Longman, 1987.