@unpublished{TUW-120835, author = {Opitz, Michael and Weber, Robert and Caissey, and Br{\"o}derbauer, Veronika}, title = {Real Time GPS- Satellite- and Receiver Clock Estimation -An interactive RTIGS WebService}, year = {2007}, note = {poster presentation: IUGG Symposium, Perugia, Italien; 2007-07-02 -- 2007-07-13} }