Morrill (2004). "Cromwell, Oliver (1599–1658)", en Oxford Dictionary of National Biography, (Oxford University Press) [2]; Worden, Blair (1985). "Oliver Cromwell and the sin of Achan". En Beales, D. y Best, G., History, Society and the Churches; Davis, J.C. (1990). "Cromwell’s religion", en Morrill, John (ed.), Oliver Cromwell and the English Revolution (Longman).
