<http://schema.org/mainEntityOfPage>
<http://www.engadget.com/2012/01/19/ibooks-2-lets-authors-set-textbook-prices-in-exchange-for-apple/True>
<http://www.engadget.com/2012/01/19/ibooks-2-lets-authors-set-textbook-prices-in-exchange-for-apple/?ncid=rss_semi>