| Hughes, Ian 31 March 2008 | The most recent changed was in , from 24 to 32 |
|---|---|
| Mueller, Frederick; Cantu, Robert; Van Camp, Steven 1996 | Scottish Journal of Political Economy |
"Procedures to determine the winner of a match or home-and-away".
22| Dart, James; Bandini, Paolo 21 February 2007 | It has been estimated that there were 22 million soccer players in the world in the early 1980s, and that number is increasing |
|---|---|
| Ingle, Sean; Glendenning, Barry 9 October 2003 | Sport Matters: Sociological Studies of Sport, Violence and Civilisation |
Illustrated History Of Football Reed International Books Limited 1996.
| "Law 3 — The Number of Players" | Alexander, Shelley 3 June 2005 |
|---|---|
| Embassy of the United States in London | Stormer, Neil 20 June 2006 |
The number of competing teams has varied over the history of the competition.
6