LIBROS. David. R. Sear, Roman Coin and their values, Ed. Spink: Vol. I, The Millenium Edition. The Republic and the Twelve Caesar 280 B.C.-AD 96, London, 2000;Vol. II, The Accession of Nerva to the overthrown of the Severan Dynasty AD-96-AD 235, London 2002; Vol. III, The Accession of Maximinus I to the death of Carinus AD 235-285, London, 2005; Vol. IV, The Tetrarchies and the rise of the House of Constantine, AD 284-337, London, 2011; Volume V, The Christian Empire: The Later Constantinian Dynasty and the Houses of Valentinian and Theodosius and their Successors, Constantine II to Zeno, AD 337-491, London, 2014.