Polit, Denise F. Nursing research : principles and methods / Denise F. Polit, Cheryl Tatano Beck. - 7th ed. - Philadelphia : Lippincott Williams & Wilkins, c2004. - xvii, 758 p. : col. ill ; 24 cm. Includes bibliographical references and index. ISBN: 0781737338 Subjects--Topical Terms: Nursing--Research--Methodology.Nursing Research--methods. Dewey Class. No.: WY 20.5 / P64 2004