HungryFEED can't get feed. Don't be mad at HungryFEED. SimplePie reported: A feed could not be found at http://yalepress.yale.edu/yupbooks/RSS/YUPNewBooks.XML. A feed with an invalid mime type may fall victim to this error, or SimplePie was unable to auto-discover it.. Use force_feed() if you are certain this URL is a real feed.