Handbook of the B.L., 6 inch 26 CWT, Mark I, Howitzer on Mark I. Travelling Carriage. (Land Service). 1917 WO 3496 - Engeland Voorschrift 40/W.O./3496 Supplement no.3 to Army/Air Operations Pamphlet no.4. (chapter 3). Carriage of Artillery. Equipment by air. Section 3, Q.F. 3.7 Howitzer, Mark 1 on carriages 3-7 … Supplement no.3 to Army/Air Operations, Pamphlet no.4. (Chapter 3). Carriage of Artillery Equipment by air. Section 8. Gun, Machine, Polsten 20 mm. Mark I on … Supplement no.3. to Army/Air Operations Pamphlet no.4 (chapter 3). Army/Air Operations Pamphlet. Carriage of Vehicles bij Air. Section 4, Q.F. 25 Ponder. Mark 2, Gun …