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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Urban sprawl across different city scales in UYR, China, from 1992 to 2015: (a–d) the four periods of 1992–1996, 1996–2002, 2002–2009, and 2009–2015, respectively.