@article {248,
	title = {Item selection in computerized adaptive testing: Improving the a-stratified design with the Sympson-Hetter algorithm},
	journal = {Applied Psychological Measurement},
	volume = {26},
	number = {4},
	year = {2002},
	pages = {376-392},
	isbn = {0146-6216},
	author = {Leung, C. K. and Chang, Hua-Hua and Hau, K. T.}
}
