↑ The Avignon Papacy, P.N.R. Zutshi, The New Cambridge Medieval History: c. 1300-c. 1415, Vol. VI, Ed. Michael Jones, (Cambridge University Press, 2000), 653.
↑ Adrian Hastings, Alistair Mason and Hugh S. Pyper, The Oxford Companion to Christian Thought, (Oxford University Press, 2000), 227.