How can I use a Google font in OJS 2?

Hello,

How can I use a Google font for a particular journal in OJS 2.4.8?

I see I can add the css in the journalStylesheet.css, but how/where can I include the <link> for the CDN Google font? (and can I do that for a single journal, or does it have to be site wide?

Thank a lot,
Gary