@article{Yuyang LI_925, author = {LI Yuyang, GU Renxu, WANG Tengfei, BI Xuecheng}, title = {Spatial evolution and mechanism of knowledge gatekeepers in the Yangtze River Delta region}, publisher = {PROGRESS IN GEOGRAPHY}, year = {2021}, journal = {PROGRESS IN GEOGRAPHY}, volume = {40}, number = {6}, eid = {925}, pages = {925-936}, keywords = {;knowledge gatekeeper;social network analysis;knowledge base;knowledge renewal;Yangtze River Delta}, doi = https://www.progressingeography.com/EN/10.18306/dlkxjz.2021.06.003 }