MicrostockGroup

When I had a website, I titled the section "Published" and included screen shots of the various publications.

I would say its fair use.  It's not uncommon for publishers to provide tear sheets to their writers and photographers.

Then just list them with perhaps a link to the web publications.

To be honest, it's not unusual NOT to display tear sheets or links. I've seen quite a few websites from (top) photographers who simply put an A-Z list down.
Of course, there may be a certain amount of untruthful claims. But I think potential clients "see through" that if the actual photography isn't that good, or the overall feel isn't professional.
Besides that, I think on the long run it'd be professional suicide to claim fake blue-chip clients. It's a relatively small industry, and one way or another things usually come out.

Back to square one... other than tearsheets: any ideas for how to phrase it?

Best so far: Google Image Search. Easy peasy via Chrome. Pics indexed are increasing all the time, so worth revisiting whenever you're at a loose end. A couple of weeks ago, the search results were off the wall, but it seems to be back to normal (good) now. Start with your best-sellers. Beware, you'll find loads of misuses (and even more image thefts, where one person has paid for the images and lots of people have lifted it from their site) and will waste a lot of emotional energy wondering what to do about them.

Also your name (you gave to the agency) +agency name, e.g. "Joe Bloggs" =iStockphoto, sometimes your username +agency (only works if they've credited you). Sometimes you get different results in different search engines.

I've got 202, screendumped in a folder, and I'm a small player.

I use "In Print" as a title for a gallery of tearsheets. While I am 'published' on many websites, I haven't added them to my In Print gallery to keep the consistency/veracity of the title:

http://www.danhowellphotography.com/#a=0&at=0&mi=2&pt=1&pi=10000&s=0&p=4