Cita APA

Leedy, P. D., & Ormrod, J. E. (2015). Practical research: Planning and design (Eleventh edition.). Pearson Education Limited.

Citación estilo Chicago

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. Eleventh edition. Harlow, Essex, England: Pearson Education Limited, 2015.

Cita MLA

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. Eleventh edition. Pearson Education Limited, 2015.