1. ‘Regarding the Plans & Sections called for of the Aden Seaward Defences’ Date: 1848/1850 Language: English Geographic region: Aden
4. Coll 6/88 'Intelligence: Military Report on Arabia (C.B. 1892).' Creator: Author: Admiralty War Staff, Naval Intelligence Division Date: 1932/1942 Language: English Geographic region: Arabian Peninsula