Zhao, Z., Zhang, Z., Wang, Z., Ferm, M., Liang, Y., & Norbäck, D. (2008). Asthmatic Symptoms among Pupils in Relation to Winter Indoor and Outdoor Air Pollution in Schools in Taiyuan, China. National Institute of Environmental Health Sciences.

Zhao, Zhuohui, Zheng Zhang, Zhuanhua Wang, Martin Ferm, Yanling Liang, and Dan Norbäck. Asthmatic Symptoms Among Pupils in Relation to Winter Indoor and Outdoor Air Pollution in Schools in Taiyuan, China. National Institute of Environmental Health Sciences, 2008.

Zhao, Zhuohui, et al. Asthmatic Symptoms Among Pupils in Relation to Winter Indoor and Outdoor Air Pollution in Schools in Taiyuan, China. National Institute of Environmental Health Sciences, 2008.