Cita APA (7th ed.)

Chang, R. Y., & Kelly, P. K. (1993). Step-by-step problem solving: A practical guide to ensure problems get (and stay) solved. Richard Chang Associates.

Cita Chicago (17th ed.)

Chang, Richard Y., i P. Keith Kelly. Step-by-step Problem Solving: A Practical Guide to Ensure Problems Get (and Stay) Solved. Irvine, Calif: Richard Chang Associates, 1993.

Cita MLA (9th ed.)

Chang, Richard Y., i P. Keith Kelly. Step-by-step Problem Solving: A Practical Guide to Ensure Problems Get (and Stay) Solved. Richard Chang Associates, 1993.