Mispelkamp , Peter K.H. “Martin Middlebrook, Convoy SC122 and HX229: Climax of the Battle of the Atlantic, March 1943 (Peter K.H. Mispelkamp) ”. The Northern Mariner Le Marin Du Nord, vol. 31, no. 1, July 2021, pp. 117-8, doi:10.25071/2561-5467.147.