Sabrina Ziebarth Nils Malzahn Heinz Ulrich Hoppe Using Data Mining Techniques to Support the Creation of Competence Ontologies. 223-230 2009 AIED http://dx.doi.org/10.3233/978-1-60750-028-5-223 conf/aied/2009 db/conf/aied/aied2009.html#ZiebarthMH09