@book{20123,
	author = {Polit, Denise F. & Beck, Cheryl Tatano},
	title = {Essentials of Nursing Research : Methods , Appraisal, And Utilization},
	publisher = {Lippincott Williams & Wilkin},
	year = {2006},
	address = {Philadephia },
	edition = {Sixth Edition},
	note = {include appendix}
}