@unpublished{TUW-120625, author = {Heinkelmann, Robert and B{\"o}hm, Johannes and Schuh, Harald and Tanir, Emine}, title = {The influence of geodetic datum definition on the VLBI reference frames}, year = {2006}, note = {poster presentation: Geod{\"a}tische Woche, M{\"u}nchen, Deutschland; 2006-10-10 -- 2006-10-12} }