the abbey issued, intended to complement the Regestum's catalogue of itsfixed ("hereditary") possessions. These massive volumes were not easy to use for the monastery's agents in property disputes, and so, when already in his seventies (in the early 1130s), Gregory composed the Liber floriger chartarum coenobii pharphensis, an index of all the abbey's properties organised topographically by churches and estates. Gregory's Liber floriger has been superseded by the indices of the modern editors of Farfa's charters. Historical work Around 1107, perceiving the need for a narrative history of Farfa to complement the documentary version he had already compiled, Gregory began an untitled work that has become known as the Chronicon Farfense. Finished in 1119, it is the primary source for the early history of the abbey. It is kept in the Biblioteca Nazionale of Italy in Rome. The Chronicon was immensely influential in "setting the tone for the writing of monastic history in Italy in the twelfth century." Among the works it influenced are the Chronicon Vulturnense, the Chronicon Novaliciense, and the Chronica monasterii Casinensis. It was itself dependent on two earlier chronicles of Farfa: the Libellus constructionis Farfensis, which covers the period from c. 700 down to the death of Abbot Hilderic, and the Destructio monasterii Farfensis, the historical work of Abbot Hugh, which continues from Hilderic's death in 857 down to Hugh's abbacy (998–1039). Besides a chronicle of Farfa's history from its foundation by Lawrence of Syria down to Gregory's day, the Chronicon also contains copies of its most important documents. In this it illustrates the purpose of all Gregory's historical works: "to defend the abbey's properties by shaping its archival and historical memory". Modern scholarly analysis In 1973 a dispute arose concerning the accuracy of Gregory's copying and his motives at the Deutsches Historisches Instut (German Historical Institute) in Rome. In 1972 Herbert Zielinski had argued that Gregory did little more than he admitted to doing in his preface to the Regestum and what he was apparently commissioned to do: correct grammatical errors. Kurze responded the next year, arguing that the "Prae-Regestum" represents the remains of a larger work which was scrapped in favour of the current Regestum, which was heavily altered by Gregory, so much so that, Kurze claimed, no edition of the charters of the eighth century was even possible. In 1982 Carlrichard Brühl, at the annual conference of the Centro italiano di studi sull'alto