@book{24954,
	author = {Polit, Denise F. and Beck, Cheryl Tatano},
	title = {Essentials of nursing research :},
	publisher = {Lippincott Williams & Wilkins,},
	year = {2006.},
	address = {Philadelphia :},
	edition = {6th edition.},
	note = {Includes bibliographical references and index.}
}