"Imperial War Museum Collection Search". Photograph number H 15191, Home Guard soldiers prepare a roadblock by inserting metal girders into pre-dug holes in the road (image). Retrieved 29 June 2012.
"Location of anti-tank ditch". South Somerset Museums and Heritage Services. Archived from the original on 3 October 2006. Retrieved 22 February 2007. A rare extant example.
Stevens 1958, pp. 27–28 Stevens, W. G. (1958). Problems of 2 NZEF. Official History of New Zealand in the Second World War 1939–45. Wellington, New Zealand: War History Branch, Department of Internal Affairs. OCLC846901610. Retrieved 24 March 2021 – via New Zealand Electronic Text Collection.
"Location of anti-tank ditch". South Somerset Museums and Heritage Services. Archived from the original on 3 October 2006. Retrieved 22 February 2007. A rare extant example.
"Nuttall Flame Thrower". The History of Wolverhampton – The City and its People. Archived from the original on 11 August 2014. Retrieved 28 July 2006.
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Collier 1957, p. 220 Collier, Basil (1957). The Defence of the United Kingdom. London: HMSO. OCLC491400913.
Stevens 1958, pp. 27–28 Stevens, W. G. (1958). Problems of 2 NZEF. Official History of New Zealand in the Second World War 1939–45. Wellington, New Zealand: War History Branch, Department of Internal Affairs. OCLC846901610. Retrieved 24 March 2021 – via New Zealand Electronic Text Collection.