The reign of Roger, and the Norman kings of Sicily, fills books of the Istoria Civile of Giannone, (tom. ii. l. xi. - xiv. p. 136 - 340,) and is spread over the ixth and xth volumes of the Italian Annals of Muratori. In the Bibliotheque Italique (tom. i. p. 175 - 122,) I find a useful abstract of Capacelatro, a modern Neapolitan, who has composed, in two volumes, the history of his country from Roger Frederic II. inclusive.