Christopher Okoro Cole jẹ́ olóṣèlú àti Ààrẹ orílẹ̀-èdè Sierra Leone tẹ́lẹ̀. London Gazette: (Supplement) no. 43670, p. 5517, 4 June 1965. Retrieved on 3 January 2015. John Stewart (1 January 2006). African States and Rulers. McFarland & Company. ISBN 978-0-7864-2562-4. https://books.google.com/books?id=I7UUAQAAIAAJ.