Leedy, P. D. (2005). Practical research planning and design Paul D. Leedy, Jeanne Ellis Ormrod. Pearson Educatin.
Čikaški stil citiranja (17. izdanje)Leedy, Paul D. Practical Research Planning and Design Paul D. Leedy, Jeanne Ellis Ormrod. Pearson Educatin, 2005.
MLA način citiranja (8. izdanje)Leedy, Paul D. Practical Research Planning and Design Paul D. Leedy, Jeanne Ellis Ormrod. Pearson Educatin, 2005.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.