Royal Signals Pocket Book. Part I. Graphical Symbols, WO 7552 - Engeland Voorschrift 26/GS Publications/1418 Field service pocket book. Part I : Conventional military symbols - Engeland Voorschrift, 26/GS Publications/931 Field service pocket book. Part II : Staff organization and staff duties in the US Army - Engeland Voorschrift, 26/GS Publications/1101 Military Intelligence Foreign Conventional Signs and Symbols. - USA Voorschrift Field Manual 30-22 Symbols for seacoast defense fire-control maps, diagrams, and structures - USA Voorschrift, Technical Regulations, No.
