Constitution of Ukraine
According to the Article 133 of Constitution of Ukraine, "the system of the administrative and territorial structure of Ukraine is composed of the Autonomous Republic of Crimea, oblasts, districts, cities, districts in city, settlements, and villages." Note, that although certain types of subdivision are not mentioned in Constitution of Ukraine (i.e. rural settlements), they are mentioned for regional composition. Also, for disambiguation regular raions (districts) are sometimes denoted as rural to distinguish them from raions in city.