The First World War in 100 Objects by Peter Doyle

History of World War I: The Western Front 1914–1916: From the Schlieffen Plan to Verdun and the Somme
by Michael S Neiberg

The First Day on the Somme: 1 July 1916
By Martin Middlebrook

Sport Heritage
edited by Gregory Ramshaw

The Greater Game: A history of football in World War I
By National Football Museum, Alexander Jackson

http://battlefields1418.50megs.com/footballerloos.htm

https://www.nationalfootballmuseum.com/collections_detail/captain-nevill-football-1916/

http://queensroyalsurreys.org.uk/new_museum/20th_century_room/Case5/The_Football.shtml