Trenton, New Jersey: Africa Research & Publications. . Wessels, Hannes (July 2010). P.K. van der Byl: African Statesman. Johannesburg: 30° South Publishers. . Wood, J.R.T. (2008). A matter of weeks rather than months: The Impasse between Harold Wilson and Ian Smith: Sanctions, Aborted Settlements and War 1965–1969. Victoria: Trafford Publishing. .
Kategoria:Historyczne państwa w Afryce nieuznawane międzynarodowo