1. Evolution of Urban Spatial Clusters in China: A Graph-Based Method Using Nighttime Light Data Wang, Congxiao; Yu, Bailang; Chen, Zuoqi; Liu, Yan; Song, Wei; Li, Xia; Yang, Chengshu; Small, Christopher; Shu, Song; Wu, Jianping 2021 Articles Cities and towns--GrowthUrbanizationCity planningSpanning trees (Graph theory)Geographic information systems