context: Several families of Byzantine Greece were of Norman mercenary origin during the period of the Comnenian Restoration, when Byzantine emperors were seeking out western European warriors. The Raoulii were descended from an Italo-Norman named Raoul, the Petraliphae were descended from a Pierre d'Aulps, and that group of Albanian clans known as the Maniakates were descended from Normans who served under George Maniaces in the Sicilian expedition of 1038.
question: Where were several Norman mercenary familes originate from?