FM 5-15 War Department Field Manual, Corps Of Engineers, Field Fortifications 1944-02-14
"Troops in occupied positions increase their combat effectiveness by works of an engineering nature called field fortifications. This manual describes field fortification methods and gives details of construction of entrenchments, emplacements, and shelters. It also outlines the principles of terrain appreciation which apply to field fortifications, and explains how to combine individual field fortifications into a unified system by means of organization of the ground. It does not cover the subject of obstacles, which is treated in FM 5-30." Digitized by the Combined Arms Research Library (CARL) Digital Library, US Army Combined Arms Center.
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