<https://forum.italiamac.it/topic/316172-amicizie-su-facebook-aggiunto-io-o-leilui/#comment-4080121>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://forum.italiamac.it/topic/316172-amicizie-su-facebook-aggiunto-io-o-leilui/>