Sources previous to the 17th century
For periods earlier than the 17th century, useful documents are rare, not systematic and difficult to access. Some towns and villages preserve lists of heads of families or hearths (rather seldom). Names of persons also appear in private acts; deeds of property (often bound in thick registers) mention many family names. All of these documents, which are handwritten and usually in Latin, are difficult to read and interpret for people lacking knowledge in palaeography.