Wang, Yukai, and Sheng Liu. “Spatial Spillover Effects of Co-Agglomeration of Producer Services on the Upgrading of Global Value Chain: Evidence from China’s Spatial Panel Data”. Frontiers in Sustainable Development 2, no. 8 (August 30, 2022): 1–7. Accessed August 20, 2026. https://bcpublication.org/index.php/FSD/article/view/1908.