@booklet {1556,
	title = {An adaptive algebra test: A testlet-based, hierarchically structured test with validity-based scoring},
	year = {1990},
	note = {Princeton NJ: Educational testing Service.},
	address = {ETS Technical Report 90-92},
	author = {Wainer, H., and Lewis, C. and Kaplan, B, and Braswell, J.}
}
