Untitled

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<script src="//code.jquery.com/jquery.min.js"></script>
<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.css" rel="stylesheet" type="text/css" />
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.2/js/bootstrap.js"></script>
  <meta charset="utf-8">
  <title>JS Bin</title>
</head>
<body>
  <a tabindex="0" role="button" data-toggle="popover" data-trigger="focus"
      class="btn"
      data-content="Popover of <a class='btn'>">
    Popover anchor w/ class 'btn'
  </a>
  
  <br><br><br>
  
  <a tabindex="1" role="button" data-toggle="popover" data-trigger="focus"
      data-content="Popover of pure <a>">
    Popover anchor w/o class 'btn'
  </a>

  <script>
    $('a[data-toggle="popover"]').popover();
  </script>
</body>
</html>