Porter, M. (Inventor), Magee, J. (Inventor), Doherty, L. (Inventor) & Wilson, I. (Inventor), 24 May 2018, IPC No. G10D 3/16 (2006.01), World Intellectual Property Organisation, Patent No. WO 2018/091399 A1, 13 Nov 2017, Priority date 15 Nov 2016, Priority No. 1619317.9