Mystery visitors

Like many website owners, I use Google Analytics to track my traffic, which I routinely check. I noticed something quite unusual this morning - this site saw a huge spike in visitors on September 23 & 24. Interestingly, these were "direct hits" i.e. rather than following a link, these visitors had simply typed "" into their web browser. This leads me to suspect a print publication - except that these visitors come from all over the globe. Which means we're dealing with a) a print publication with outstanding international distribution, or b) an online publication which doesn't hyperlink sites it references, or c) some other kind of media e.g. radio, tv, or a podcast.
Can anyone enlighten me? What was published on September 23 that referenced Expert Sleepers? Post a comment on the blog, or email me, if you know.