Georg Klinker Marc Linster David Marques John P. McDermott Gregg Yost Exploiting problem descriptions to provide assistance with the Sisyphus task. 293-314 1994 40 Int. J. Hum.-Comput. Stud. 2 http://dx.doi.org/10.1006/ijhc.1994.1014 db/journals/ijmms/ijmms40.html#KlinkerLMMY94