@unpublished{TUW-120235, author = {Krankowski, A. and Schuh, Harald and Kosek, W. and Hobiger, Thomas and Popinski, W}, title = {Comparison of the Total Electron Content obtained for GPS and VLBI observations}, year = {2005}, note = {talk: EGU 2005, Vienna; 2005-04-24 -- 2005-04-29} }