@unpublished{TUW-274874, author = {Natras, Randa and Halilovic, Dzana}, title = {Latitudinal and Seasonal Dependence of Geomagnetic Storm Effects on the Ionospheric TEC and Positioning Accuracy in Europe in 2015}, year = {2018}, note = {poster presentation: International Workshop on GNSS Ionosphere, Shanghai; 2018-11-04 -- 2018-11-06} }