John F.J.F.ClarkJohn F.J.F., Petroleum revenues and political development in the Congo Republic: the democratic experiment and beyond, [w:] MatthiasM.Basedau, Resource Politics in Sub-Saharan Africa, GIGA-Hamburg, 2005, s. 138–139, ISBN 978-3-928049-91-7 [dostęp 2020-05-14](ang.).