Sun, J., Guo, X., Zhang, J., Jia, C., & Xu, A. (2013). Suicide rates in Shandong, China, 1991–2010: Rapid decrease in rural rates and steady increase in male–female ratio. Journal of Affective Disorders, 146(3), 361–368. http://doi.org/10.1016/j.jad.2012.09.020