I have, over the years, published a number of works on the coinage of the third century. Below is a bibliography of those works and I intend to make most of them available as pdf downloads from this page. This is a work in progress so please keep checking for updates.
Aspects of the Relationship between the Central and Gallic Empires in the mid to late Third Century AD BAR Int Ser 963 (2001)
‘An unrecorded Constantinian London mint type’ Numismatic Circular 101 (1993) p.196
‘Tetrican epigraphy – some thoughts’ Numismatic Circular 103 (1995) p.261
‘Claudius II altar types’ Numismatic Circular 104 (1996) p.6