RSS source 元素

<?xml version="1.0" encoding="ISO-8859-1" ?>
<rss version="2.0">

<channel>
  <title>W3CSchool Home Page</title>
  <link>http://www.w3cschool.cn</link>
  <description>Free web building tutorials</description>
  <item>
    <title>RSS Tutorial</title>
    <link>//www.w3cschool.cn/rss</link>
    <description>New RSS tutorial on W3CSchool</description>
    <source url="http://www.w3cschool.cn">W3CSchool.com</source>
  </item>
</channel>

</rss>