Rex Sacrorum, the office of the highest-ranking priest under the Roman Kingdom
A copy was edited in the Sacrorum Conciliorum nova et amplissima collectio of Giovanni Domenico Mansi in the 18th century, and more recently a new edition has been published by Benjamin Z. Kedar in Speculum (Vol. 74, 1999).
With the aid of many of his Order, he edited the first concordance of the Bible (Concordantiae Sacrorum Bibliorum or Concordantiae S. Jacobi), but the assertion that we owe the present division of the chapters of the Vulgate to him is false.