See also
   http://www.hixie.ch/tests/evil/mixed/cascade/httplink.html
   http://www.hixie.ch/tests/evil/mixed/cascade/acidlinkcascade.html
   http://www.hixie.ch/tests/evil/mixed/cascade/altcascade.html
   http://www.hixie.ch/tests/evil/mixed/cascade/minialtcascade.html