Ground based FTIR measurements of O₃, HF, HCl, ClONO₂, and HNO₃ at Kiruna (Sweden) since winter 1993/94 - Blumenstock, T.; Hase, F.; Fischer, H.; Ruhnke, R.; Stiller, G.; Yashkov, D.; Meier, A.; Steen, A.; Kondo, Y. (2000)