About Gilbert "Buatère" (Buttericus) Drengot, di Aversa
One of five Norman brothers who left Normandy (apparently because this Gilbert was charged with the murder of a Vicomte named GuillaumeRepostel) and fled to southern Italy, establishing a Norman presence in Aversa.
Orderic Vitalis (XXVI, 47) records that Osmand Drengot killed Guillaume Repostel while hunting in the forest at the court of Duke Robert of Normandy after Repostel boasted loudly of having seduced Drengot's daughter. Other accounts (Aimé du Montcassin et Pierre le Diacre) say it was Osmond's brother Gilbert. In any case, all five brothers fled to Rome for an audience with the Pope, and there they met Melo de Bari, who apparently became their protector in Italy.
GILBERT "Buatère" (-[after 1022]). The Chronica Monasterii Casinensis records that "Giselbertus…qui et Buttericus" killed "Guilielmus cognomento Repostellus", for which he was banished by "Robbertus comes", and that "Giselbertus…[cum] quatuor fratribus suis, Rainulfo, Asclittino, Osmundo, atque Rodulfo" arrived in Capua where they joined "Melus", dated to [1015/16] from the context. According to Amatus, Gilbert Buatère threw William from a very high place and killed him, took over William's position as viscount, but fled to Italy with his four brothers when sentenced to death. Amatus also records how the brothers helped Melus fight the Greeks in Apulia. The Chronica Monasterii Casinensis records that "Stephano autem, Melo et Petro nepotibus præfati Melo" were granted "comitatum Cominensis" (by Emperor Heinrich II) together with "in auxilium Normannos, Giselbertum, Gosmannum, Stigandum, Torstainum balbum, Gualterium de Canosa et Ugonem Falluccam, cum aliis decem et octo", dated to  from the context. Chalandon identifies these Normans as "Gilbert, Osmond, Asclettin, Toustain le Bègue, Gautier de Canisy et Hugues Falluca".