<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet title="xslformating" type="text/xsl" href="example4.xsl"?>
<!DOCTYPE html
[
  <!ENTITY mailto "mailto:">
  <!ENTITY username "gabriel">
  <!ENTITY arobase "@">
  <!ENTITY hostname "gabsoftware">
  <!ENTITY tld ".com">
  <!ENTITY http "http://">
  <!ENTITY www "www.">
  <!ENTITY email "&username;&arobase;&hostname;&tld;">
  <!ENTITY website "&http;&www;&hostname;&tld;">
]>
<html xml:lang="en">
  <head>
    <title>Extending XHTML - Example 4</title>
    <meta http-equiv="Content-Type" content="application/xhtml+xml; charset=utf-8" />
  </head>
  <body>
    <p>
      This email is obfuscated : <a href="&mailto;&email;">&email;</a>
    </p>
  </body>
</html>