Wiwanitkit, Viroj. “Letter to the Editor: Human Infections With Avian Influenza A(H7N9) Virus: Preliminary Assessments of the Age and Sex Distribution”. Western Pacific Surveillance and Response 4, no. 4 (October 31, 2013). Accessed May 12, 2024. https://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/216.