http://www.cx-portal.com/_smb/wti.php
http://www.cnbc.com/2016/03/16/april-oil-freeze-meeting-may-go-ahead-without-iran-report.html
http://www.marketwatch.com/story/opec-oil-output-falls-90000-barrels-a-day-in-february-platts-2016-03-15
http://www.shanghaidaily.com/article/article_xinhua.aspx?id=323465