Ground-based microwave observation and model calculations of ozone depletion in the arctic atmosphere due to the solar proton events in October/November 2003 - Kopp, G.; Palm, M.; Hochschild, G.; Notholt, J.; Raffalski, U.; Reddmann, Th.; Ruhnke, R.; Sinnhuber, M.; Wiehle, M. (2006)