@article {xenos2002survey, title = {A survey on student dropout rates and dropout causes concerning the students in the Course of Informatics of the Hellenic Open University}, journal = {Computers \& Education}, volume = {39}, number = {4}, year = {2002}, pages = {361{\textendash}377}, publisher = {Elsevier}, author = {Xenos, Michalis and Christos J. Pierrakeas and Pintelas, Panagiotis} }