Saint-Evroul Abbey were centres of musical production and education. At Fécamp, under two Italian abbots, William of Volpiano and John of Ravenna, the system of denoting notes by letters was developed and taught. It is still the most common form of pitch representation in English- and German-speaking countries today. Also at Fécamp, the staff, around which neumes were oriented, was first developed and taught in the 11th century. Under the German abbot Isembard, La Trinité-du-Mont became a centre of musical composition. At Saint Evroul, a tradition of singing had developed and the choir achieved fame in Normandy. Under the Norman abbot Robert de Grantmesnil, several monks of Saint-Evroul fled to southern Italy, where they were patronised by Robert Guiscard and established a Latin monastery at Sant'Eufemia Lamezia. There they continued the tradition of singing. Rulers List of Dukes of Normandy List of Counts and Dukes of Apulia and Calabria List of Counts of Aversa List of Princes of Capua List of Dukes of Gaeta List of Princes of Taranto List of monarchs of Sicily List of Princes of Antioch List of Officers of the Principality of Antioch Second House of Lusignan List of English Monarchs List of Scottish monarchs See also Bailiwick of Guernsey Bailiwick of Jersey Channel Islands Cotentin Peninsula House of Normandy Norman language Norsemen Rus' people References Sources Primary . . Secondary . . . (feudal Saxons) (Saxon social demotions) (Mudrum fine) Further reading External links . , English translation. . . .