^Casert, Raf (August 10, 2017). "Makwala reaches 200 final at world championships". The Sentinel. Vol. 157, no. 42. Carlisle, Pennsylvania: Lee Enterprises. Associated Press. p. B3 – via Newspapers.com. The biggest surprise on a cold and wet night came in the 400 hurdles. Karsten Warholm of Norway held off Yasmani Copello of Turkey and Kerron Clement of the United States for gold.
^ abc"Norway". IAAF World Championships London 2017. IAAF. Retrieved 9 Oct 2019.