Double and triple ionisation of isocyanic acid by Eland, JHD, Squibb, RJ, Sterling, AJ, Wallner, M, Roos, AH, Andersson, J, Axelsson, V, Johansson, E, Teichter, A, Stranges, S, Brunetti, B, Dyke, JM, Duarte, F, R Feifel