Richard Earl is Director of Undergraduate Studies in the Mathematical Institute, University of Oxford, and Senior Mathematics Tutor at Worcester College, Oxford. He has taught a range of pure and applied mathematics at undergraduate and graduate level, specializing in algebra, geometry, and topology, as well as presenting various mathematics to secondary school students at masterclasses and summer schools. He is the author of Towards Higher Mathematics: A Companion (CUP, 2017), and Topology: A Very Short Introduction (OUP, 2019).

James Nicholson has a mathematics degree from Cambridge, and taught at Harrow School for twelve years before becoming Head of Mathematics at Belfast Royal Academy in 1990. From 2003 he has worked mostly with the School of Education at Durham University and as an education consultant for a variety of organizations. He is the author of four A-level Statistics texts, two GCSE Mathematics revision guides, and he is a contributing author for a number of other mathematics textbooks.