instructors to ensure that their recruits have memorised and are able to recite all of their regiment's battle honours. Such methods are meant to bring the new soldier into the regimental ethos and sub-culture by means of imprinting shared history. In some cases where a battle honour was not granted, a special distinction has been substituted. For example, soldiers of The Rifles wear a cap badge on both the front and the rear of their hats. This so-called "back badge" is unique in the British Army and was awarded to the 28th Regiment of Foot for their actions at the Battle of Alexandria in 1801. Knowledge of that battle honour, represented by the back badge, is said to have encouraged the soldiers of the Gloucestershire Regiment in the defence of Gloster Hill during the Battle of the Imjin River in April 1951 during the Korean War. Other uniform distinctions include: Oakleaf Shoulder Badge (The Calgary Highlanders, The Canadian Scottish Regiment (Princess Mary's) and The Royal Winnipeg Rifles), awarded for "Kitcheners' Wood" in April 1915. No battle honour had been granted and the units petitioned for a special badge. Sphinx: Several British regiments have a sphinx on their regimental colour as well as cap badges and belt buckles to commemorate service in Egypt, specifically the Battle of Alexandria in 1801. Eagle: The Royal Scots Dragoon Guards have an eagle on their cap badge to commemorate the capture of a French Imperial Eagle at Waterloo by the Royal Scots Greys. The Blues and Royals similarly wear an eagle as a shoulder badge commemorating the Eagle captured at Waterloo by the Royal Dragoons. Overseas awards to British military units Subject to approval by the sovereign, awards made by other allied nations may be permitted to be worn or carried. For example, several units have been awarded the French Croix de guerre 1914–1918 and Croix de guerre 1939–1945, the ribbon of which can be worn on the uniform. The United States Presidential Unit Citation, as with other similar citations, is similarly worn on the uniform (usually on the arm), but is also carried on the colour or guidon of the unit it has been awarded to. In the Commonwealth, three units are permitted to carry this award on their Regimental Colour: 2nd Battalion, Princess Patricia's Canadian Light Infantry 3rd Battalion, Royal Australian Regiment D Company, 6th Battalion, Royal Australian Regiment (Awarded to D Company