Holmen, S.E., M.E. Dyrland, and F. Sigernes (2014), Mesospheric temperatures derived from three decades of hydroxyl airglow measurements from Longyearbyen, Svalbard (78°N), Acta Geophysica, Vol 62, No 2, pp. 302-315, doi.org/10.2478/s11600-013-0159-4 (pdf)