angular-ui/bootstrap — pull request #238 by millette (2013-03-18 11:24:22+00:00)
Title: Fixed typo (buttons-checkbox -> buttons-radio)

According to http://twitter.github.com/bootstrap/javascript.html#buttons the 2nd example should use "buttons-radio" as data-toggle. I tried in plunker but it didn't make a difference (even worked without the data-toggle attribute). But it still looks like a copy/paste error.