“…(for more information, including the schemes, see Klapka et al, 2013a). Functional regions are usually understood to be the areas organised by the horizontal functional relations (flows, interactions) that are maximised within a region and minimised across its boundaries, so that the principles of internal cohesiveness and external separation regarding spatial interactions are met (for example, see Smart, 1974;Karlsson, Olsson, 2006;Farmer, Fotheringham, 2011;Klapka et al, 2013a).…”