Cory J. Butz Shan Hua R. Brien Maguire A web-based bayesian intelligent tutoring system for computer programming. 77-97 2006 4 Web Intelligence and Agent Systems 1 http://iospress.metapress.com/openurl.asp?genre=article&issn=1570-1263&volume=4&issue=1&spage=77 db/journals/wias/wias4.html#ButzHM06