Brynildsen, N., Brekke, P., Fredvik, T., Haugan, S. V. H., Kjeldseth-Moe, O., Maltby, P., Harrison, R. A., Pike, C. D., Rimmele, T., Thompson, W. T., & Wilhelm, K. (1998). EUV spectroscopy of the sunspot region NOAA 7981 using SOHO. I. Line emission and time dependence. Solar Physics, 179, 43-74.