The EUV spectrum of the Sun: long-term variations in the SOHO CDS NIS spectral responsivitiesG. Del Zanna, V. Andretta, P. C. Chamberlin, T. N. Woods and W. T. ThompsonA&A, 518 (2010) A49DOI: https://doi.org/10.1051/0004-6361/200912904
