Magnetic field design in a cylindrical high-permeability shield: The combination of simple building blocks and a genetic algorithm. - Packer, M.; Hobson, P. J.; Davis, A.; Holmes, N.; Leggett, J.; Glover, P.; Hardwicke, N. L.; Brookes, M. J.; Bowtell, R.; Fromhold, T. M. (Journal of Applied Physics, 2022)