1. 'Agreement relating to the Kalba Oil Concession [between] His Majesty's Government in the United Kingdom and Petroleum Development (Trucial Coast) Limited' Date: 1940/1940 Language: English Geographic region: Kalba
2. 'CONFIDENTIAL VOL. B.58. 86/7-X P.C.L. TRUCIAL COAST' Date: 1938/1941 Language: English Geographic region: Abu DhabiAjmanKalba
3. Coll 30/147 'Trucial Coast: Kalba Affairs & Succession' Date: 1936/1948 Language: English Geographic region: Kalba