How to center .btn-group from twitter-bootstrap?

Adding text-center to a parent works for me (Bootstrap 3):

<div class="text-center">
   <div class="btn-group">
      <a href=1 class="btn btn-small">1</a>
      <a href=1 class="btn btn-small">2</a>
      <a href=1 class="btn btn-small">3</a>
   </div>
</div>