@book{11944,
	author = {Sigelman, Carol K.},
	title = {Life-span human development /},
	publisher = {Cengage Learning},
	year = {2015},
	address = {Boston},
	edition = {Nineth edition},
	url = {http://www.loc.gov/catdir/enhancements/fy1515/94006251-b.html}
}