Purtill, Richard L. (1997) ‘Defining Miracles’ in In Defence of Miracles: A Comprehensive Case for God’s Action in History ed. by R Douglas Geivett and Gary R Habermas (Leicester: Apollos) p67. Hume’s argument remains influential, particularly as taken up by Antony Flew in ‘Neo-Humean arguments about the miraculous’ - In Defence of Miracles pp45-57.