Visit of Secretary of State to Aden, 1961 [recommended replies to the Federal rulers and background regarding Anglo-Yemeni relations and future developments in the Yemen] 3 Apr 1961 typ Secret
South-west Arabia (The Yemen and the Aden Protectorate) Transliteration of names Third edition [revised by Lt-Col M C Lake] System-RGS II London: Colonial Office, Oct 1941
Brief notes on the history of the tribes now residing in the Eastern Aden Protectorate, and their present area and divisions, as at Oct 1, 1952 (corrected to 1 July 1955) Maj I E Snell, with 2 appendices by Cpt J N Ellis, Brief notes on the way of life and economic conditions of the different tribes of the Eastern Aden Protectorate as at Oct 1 1952 (corrected to 1 July 1955) Maj I E Snell Aden, 1955 typ