@book{6489,
	author = {Gravetter, Frederick J. and Forzano Lovi-Ann B.},
	title = {Understanding Research methods for the bevaioral science /},
	publisher = {Cengage Learning Asia,},
	year = {2012.},
	address = {Singapore :},
	edition = {2nd},
	note = {Includes bibliographic references and index}
}