Schwabe, Julian, and Markus Hassler. “The Impact of Periodic Air Pollution Peaks in Beijing on Air Quality Governance in China”. DIE ERDE – Journal of the Geographical Society of Berlin 147, no. 1 (March 22, 2016): 53-65. Accessed June 28, 2022. https://www.die-erde.org/index.php/die-erde/article/view/255.