Polit, Denise F. Essentials of nursing research : methods, appraisal, and utilization / Denise F. Polit, Cheryl Tatano Beck - 6th ed. - Philadelphia : Lippincott Williams & Wilkins, 2003 - 554 p. ; 23 cm. Includes bibliographical references and index. ISBN: 9780781749725 Subjects--Topical Terms: Nursing--Research