Delahaye, F, Badnell, N R, Ballance, C P, Palmeri, P, Preval, S, Quinet, P, Ramsbottom, C, Smyth, R T, Turkington, M & Zeippen, C J 2018, A quantitative comparison of opacities calculated using the distorted-wave and R-Matrix methods . in C Mendoza, S Turck-Chieze & J Colgan (eds), Workshop on Astrophysical Opacities: proceedings of a workshop held at Fetzer Center, Western Michigan University, Kalamazoo, MI, 1-4 August 2017 . Astronomical Society of the Pacific Conference Series, vol. 515, Astronomical Society of the Pacific, pp. 69-78 .