@unpublished{TUW-219245, author = {Weber, Robert and Montenbruck, Oliver and Steigenberger, Peter and Hugentobler, Urs and Khachikyan, Robert}, title = {The IGS Multi-GNSS Experiment (MGEX)}, year = {2013}, note = {talk: The European Navigation Conference, Vienna, Austria; 2013-04-23 -- 2013-04-25} }