<http://schema.org/thumbnailUrl>
<http://i0.wp.com/www.gottabemobile.com/wp-content/uploads/Retweet-email-notification-twitter.png?fit=150%2C150>
<http://www.gottabemobile.com/2011/05/31/how-to-turn-off-twitter-emails-for-replies-retweets-and-favorites/>