1. For surveys of the Easter Controversy see Bonnie Blackburn and Leofranc Holford-Strevens, The Oxford Companion to the Year (Oxford, 1999), pp. 791–828; Bede, The Reckoning of Time, ed. and trans. Faith Wallis (Liverpool, 1999), pp. xxxv–lxiii;
2. Thomas Charles-Edwards, Early Christian Ireland (Cambridge, 2000), pp. 391–415;
3. George Declercq, Anno Domini: The Origins of the Christian Era (Turnhout, 2000);
4. Leofranc Holford-Strevens, History of Time: A Very Short Introduction (Oxford, 2005), pp. 44–63;
5. Alden Mosshammer, The Easter Computus and the Origins of the Christian Era (Oxford, 2008).