<http://schema.org/description>
"An excellent WebmasterWorld thread named Top 3 PPC: Where does AdWords Rank for You ranks the three top players, Google AdWords, Yahoo Search Marketing &amp; Microsoft adCenter against each other.  The ra"^^<http://www.w3.org/2001/XMLSchema#string>
<https://www.seroundtable.com/archives/006036.html>