<http://schema.org/mainEntityOfPage>
<http://www.upi.com/Science_News/2013/10/04/Aurora-borealis-lights-Northern-US-in-spectacular-show/6141380887424/>
<http://www.upi.com/Science_News/Blog/2013/10/04/Aurora-borealis-lights-Northern-US-in-spectacular-show/6141380887424/?st_rec=3611381331621>