Editing Region (section)

===Functional regions===
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 borders so that the principles of internal cohesiveness and external separation regarding spatial interactions are met (see, for instance, Farmer and Fotheringham, 2011;<ref>{{cite journal|last1=Farmer|first1=CJQ|last2=Fotheringham|first2=AS|title=Network-based functional regions|journal=Environment and Planning A|date=2011|volume=43|issue=11|pages=2723–2741|doi=10.1068/a44136|bibcode=2011EnPlA..43.2723F |s2cid=144055983}}</ref> Klapka, Halas, 2016;<ref>{{Cite journal|last1=Klapka|first1=P|last2=Halas|first2=M|date=2016|title=Conceptualising patterns of spatial flows: five decades of advances in the definition and use of functional regions|journal=Moravian Geographical Reports|volume=24|issue=2|pages=2–11|doi=10.1515/mgr-2016-0006|doi-access=free|bibcode=2016MorGR..24....2K}}</ref> Smart, 1974<ref>{{cite journal|last1=Smart|first1=MW|title=Labour market areas: uses and definition|journal=Progress in Planning|date=1974|volume=2|pages=239–353|doi=10.1016/0305-9006(74)90008-7|bibcode=1974ProgP...2..239S }}</ref>). A functional region is not an abstract spatial concept, but to a certain extent it can be regarded as a reflection of the spatial behaviour of individuals in a geographic space. 
The functional region is conceived as a general concept while its inner structure, inner spatial flows, and interactions need not necessarily show any regular pattern, only selfcontainment. The concept of self-containment remains the only crucial defining characteristic of a functional region. Nodal regions, functional urban regions, daily urban systems, local labour-market areas (LLMAs), or travel-to-work areas (TTWAs) are considered to be special instances of a general functional region that need to fulfil some specific conditions regarding, for instance, the character of the region-organising interaction or the presence of urban cores, (Halas et al., 2015<ref>{{cite journal|last1=Halas|first1=M|last2=Klapka|first2=P|last3=Tonev|first3=P|last4=Bednar|first4=M|title=An alternative definition and use for the constraint function for rule-based methods of functional regionalisation|journal=Environment and Planning A|date=2015|volume=47|issue=5|pages=1175–1191|doi=10.1177/0308518X15592306|bibcode=2015EnPlA..47.1175H|s2cid=143263476}}</ref>).