^"The fact that initially the SAS would operate only in South Armagh was an illustration of the seriousness of the situation there and tacit acceptance of the fact that normal soldiering and fieldcraft skills were proving inadequate. This had been brought home by the incident in which the three fusiliers had been killed when their Observation Post (OP) had been attacked in 1975. The Army follow up report identified a number of basic errors. The OP had been established in darkness on a slope at Drummuckavall behind bushes overlooking a small stream running along the border. Lance Corporal Johnson and three fusiliers had been bunched together on a single site, which was exposed and within sight of several houses. None of the soldiers was wearing a combat jacket or head net and a groundsheet had been flapping in the breeze. 'Remember, in South Armagh it is no use removing local vegetation to provide cover, locals will soon spot that' the report said, before concluding that the casualties had been the result of 'bad camouflage, wrong routine and incorrect OP layout." Harnden (2000), p.159
^Ripley, Tim and Chappel, Mike (1993). Security forces in Northern Ireland (1969–92). Osprey, p. 46. ISBN1-85532-278-1
^"The fact that the SAS would initially operate only in South Armagh was an illustration of the situation there and tacit acceptance of the fact that normal soldiering and fieldcraft skills were probing inadequate." Harnden (2000), p. 159