function sprache ()
{
  switch(document.sprachwahl.sprachwahlfeld.value)
  {
    case "de":
        top.location.href = "../de/index.html";
        break;
    case "en":
        top.location.href = "../en/index.html";
        break;
    case "fr":
        top.location.href = "../fr/index.html";
        break;
    case "cn":
        top.location.href = "../cn/index.html";
        break;
   }
}