APA (7th ed.) Citation

Amsden, R. T., & Butler, H. E. (1989). SPC simplified: Practical steps to quality. Quality Resources.

Chicago Style (17th ed.) Citation

Amsden, Robert T., and Howard E. Butler. SPC Simplified: Practical Steps to Quality. New York: Quality Resources, 1989.

MLA (9th ed.) Citation

Amsden, Robert T., and Howard E. Butler. SPC Simplified: Practical Steps to Quality. Quality Resources, 1989.