Gaya APA

Polit, D, F., Beck, C, T. (2003). Nursing Research Principles and Methods Seventh Edition (ed.7.--). : Lippincott williams & Wilkins.

Gaya MLA

Polit, Denise, F.., Beck, Cheryl, Tatano. "Nursing Research Principles and Methods Seventh Edition". ed.7.-- : Lippincott williams & Wilkins, 2003. Text.