Quick question about html menu/list

Im using an easy drop down list to have some links on and I want the links to open in an iframe on the site (I.e how do I point the target to the iframe)

How do I do that?

this is the code


<form action="" name="choose" class="sortimentform">
<select name="channels" onChange="window.location=(''+this.options[this.selectedIndex].value)" class="sortimentform">
      <option value="/" class="sortimentform" selected>Leverantörshemsidor A-Ö</option>
      <option value="http://www.">Artemide</option>
      <option value="http://www.">Artemide</option>
      <option value="http://www.">Artemide</option>
      <option value="http://www.">Artemide</option>
      <option value="http://www.">Artemide</option>
      <option value="http://www.">Artemide</option>
      

  </select><br />
              </form>