Yan, W., Cheng, L., Tan, L., Yu, M., Nie, S., Xu, B., Palm, L. and Diwan, V. (2013) “Using Medications Sales from Retail Pharmacies for Syndromic Surveillance in Rural China”, Online Journal of Public Health Informatics, 5(1). doi: 10.5210/ojphi.v5i1.4490.