Icons doesn't appear in accordion method

Icons doesn't appear in accordion method

Hi,
I've downloaded whole jQuery-Ui package, to use accordion UI. This is the source code of my page:
  1. <!DOCTYPE html>
    <html>
    <head>
    <meta charset="utf-8">
    <title>.:jQuery-ui:.</title>
    <script src="jquery-ui/external/jquery/jquery.js"></script>
    <script src="jquery-ui/jquery-ui.min.js"></script>
    <link rel="stylesheet" href="jquery-ui/jquery-ui.min.css">
    <body>
    <div id="accordion">
        <h3>Section 1</h3>
        <div>sgoihaogiha giohag oaighaiog haouigh auioghag</div>
        <h3>Section 2</h3>
        <div>osguaoigjhaoigh agiohagiohagio ahgio ahgiohg</div>
        <h3>Section 3</h3>
        <div>soighoigh goihago ihago aihgoiagh ioaghoaihaio gag</div>
    </div>
    <script type="text/javascript">
    $('#accordion').accordion({collapsible:true, active:false, icons:{ "header": "ui-icon-triangle-1-e", "activeHeader": "ui-icon-triangle-1-s" }});
    </script>
    </body>
    </head>
    </html>
The problem is that the icons that should appear, never appears, someone can try this code and tell me why and what's the solution?