<http://schema.org/headline>
"\u30D5\u30EA\u30FC\u30BD\u30D5\u30C8\u3067\u3067\u304D\u308BPDF\u7DE8\u96C6\uFF1A\u65B0\u520A\u30D4\u30C3\u30AF\u30A2\u30C3\u30D7"^^<http://www.w3.org/2001/XMLSchema#string>
<http://gihyo.jp/book/pickup/2013/0086>