copy, distribute and/or modify this document under the terms of the GNU Free
Documentation License, Version 1.1 or any later version published by the
Free Software Foundation; with the Invariant Sections being ``Prefazione'',
copy, distribute and/or modify this document under the terms of the GNU Free
Documentation License, Version 1.1 or any later version published by the
Free Software Foundation; with the Invariant Sections being ``Prefazione'',