User:Kamrynkinsey/citing sources

'''Population density and excessive vehicle usage is a major contributor to air pollution in China. Research found during the COVID-19 pandemic on air quality in 10 Chinese mega-cities backs this up, as there was a significant improvement in air quality during the outbreak period compared to previous years.'''


 * 1) Crystal Jane Ethan, Kingsley Katleho Mokoena, and Yan Yu* Air Pollution Status in 10 Mega-Cities in China during the Initial Phase of the COVID-19 Outbreak https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003380/