Leedy Paul D. (2001). Practical Research Planning and Design. Merrill Prentice Hall.
Čikaški stil citiranja (17. izdanje)Leedy Paul D. Practical Research Planning and Design. MPH: Merrill Prentice Hall, 2001.
MLA način citiranja (9. izdanje)Leedy Paul D. Practical Research Planning and Design. Merrill Prentice Hall, 2001.
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