@unpublished{TUW-253320, author = {Kealy, Allison and Gikas, Vassilis and Retscher, G{\"u}nther}, title = {Recent Developments on Multi-Sensor Systems within the IAG as a Driver for Robust Positioning and Navigation}, year = {2016}, note = {invited; talk: IAG Commission 4 Symposium, Wroclaw, Polen; 2016-09-04 -- 2016-09-07} }