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2. GEDMatch.https://www.gedmatch.com/. Accessed 11 Sept 2020.
3. Familial DNA Testing Scores a Win in Serial Killer Case
4. Xinhua News Agency.Distant cousin's DNA locked up the suspect Gao Chengyong.http://www.xinhuanet.com/politics/2016‐08/30/c_129261666.htm. Accessed 11 Sept 2020.
5. New York Times.Man thought to be China’s Jack the Ripper Is arrested.https://www.nytimes.com/2016/08/30/world/asia/china‐jack‐the‐ripper‐gao‐chengyong.html. Accessed 11 Sept 2020.