<https://www.culture-nature-magazine.info/wordpress/28/tentativi-per-salvare-cio-che-resta-del-lago-ciad/africa/silvia/#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.culture-nature-magazine.info/wordpress/28/tentativi-per-salvare-cio-che-resta-del-lago-ciad/africa/silvia/>