<http://schema.org/keywords>
"jon wertheim mailbag si sportsperson of the year serena williams sportsperson of the year serena williams sports illustrated sportsperson of the year roger federer martina hingis roger federer serena williams american pharoah"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.si.com/tennis/2015/12/16/mailbag-serena-williams-sportsperson-debate>