@unpublished{TUW-120420, author = {Frank, Andrew U.}, title = {Information Imperfection: The Ontological of Data Quality}, year = {2006}, note = {talk: Informatik-Kolloquium, FernUniversit{\"a}t Hagen, Fakult{\"a}t f{\"u}r Mathematik und Informatik; 2006-10-18} }