Changes

*[http://1914-1918.invisionzone.com/ Great War Forum] is a message board for the First World War which was originally part of the website "The Long, Long Trail", but is now a separate, independent entity.

*[http://www.epsomandewellhistoryexplorer.org.uk/MedicalCategories.html British Army Medical Categories 1914]. The criteria subsequently changed at various times throughout the War.<ref>Muerrisch [Langley, David]. [http://1914-1918.invisionzone.com/forums/index.php?/topic/98707-level-of-fitness-needed-for-service/&do=findComment&comment=2463769 level of fitness needed for service] ''Great War Forum'' 14 November 2016. Retrieved 14 November 2016.</ref>

*[http://www.westernfrontassociation.com/ The Western Front Association (WFA)] Although the main emphasis is on the Western Front, other areas are also included.

*[http://www.gwpda.org/ The World War I Document Archive] gwpda.org