APA Style

Polit, D, F., Hungler, B, P. (1999). Nursing Research : Principles and Methods (Ed. 6). Philadelphia: Lippincott.

MLA Style

Polit, Denise, F.., Hungler, Bernadette, P.. "Nursing Research : Principles and Methods". Ed. 6 Philadelphia: Lippincott, 1999. Text.