<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2013/08/27/130827031243_plaque__304x171__nocredit.jpg>
<http://www.bbc.com/indonesia/majalah/2013/08/130827_iptek_wabah_bubonik.shtml>