We include as much information as we can about referrers to your site, but sometimes the information we receive about those referrals doesn’t include the specific page that is linking to your blog.
One way you can try to find that precise link is by searching within a site or domain in Google. For example, if you know that yourgroovydomain.com is a referrer, you can search Google for “site:yourgroovydomain.com” along with your blog’s title or URL to try to find out which page on that domain links to your blog.
That was the answer I hoped not to see. In a recent post my referrers tripled from Facebook, but no one in my immediate community shared my blog. Was hoping I might have tracked down the traffic source. Oh well. Thanks for being happiness engineers.