1Associated Press. "Murder of Soccer Player after Own-Goal 20 Years Ago Still Resonates in Colombia." Fox News: World, July 02, 2014. Accessed: January 31, 2018.
2Asta, Eduardo. "Maracanã fica mais moderno sem abrir mão de sua história." Estadão.com: Esportes. September 15, 2012. Accessed: January 31, 2018.
3Boehm, Charles. "FIFA Announces Ticket Prices for 2018 World Cup, 2017 Confederations Cup." Major League Soccer. July 11, 2016. Accessed: January 31, 2018.
4"FIFA World Cup Players Statistics." FIFA.com. 2018. Accessed: January 31, 2018.
5Gardner, Paul. The Simplest Game: The Intelligent Fan's Guide to the World of Soccer. New York: Macmillan Publishing Company, 1994.
6Goldblatt, David, and Johnny Acton. The Soccer Book: The Sport, The Teams, The Tactics, The Cup. London: DK Publishing, 2009.
7"Key Statistics." US Youth Soccer. 2012. Accessed: January 30, 2018.
8Kruschewsky, Gabriela. "Wake Up, America: Here’s Why Soccer Is the World’s Best Sport." Huffington Post, May 14, 2014. Accessed: January 31, 2018.
9Lisi, Clemente Angelo. A History of the World Cup: 1930–2006. Lanham, MD: Scarecrow Press, 2007.
10Smith, Matthew Nitch. "The 18 Biggest Soccer Stadiums in the World." Business Insider, May 07, 2016. Accessed: January 31, 2018.
11Walker, Chris. "Soccer's Global Dominance of Sports, in 3 Simple Charts." MIC Network Inc. June 11, 2014. Accessed: January 31, 2018.