6. See Chapters 4, 5 and 6 below.

7. Malcolm Lambert, The Cathars, Blackwell, Oxford, 1998, p. 4.

8. See Jonathan Sumption, The Albigensian Crusade, Faber and Faber, London, 1999, pp. 28–30. See also Arthur Guirdham, The Great Heresy: the History and Beliefs of the Cathars, C. W. Daniel Company Ltd., Saffron Walden, 1993, p. 23.