function homeMarktscan() {

    var land_marktscan = document.getElementById("land_marktscan").value;

    if (land_marktscan == '') {
      document.getElementById("land_marktscan").className = "input_home_marktscan_fout";
      }

    else {
      var url_to_open = "/producten.php";
      url_to_open =
      window.location=('http://www.baandersconsultancy.nl/producten.php?ID=006&NAV_TAB=002&LAND_MARKTSCAN=' +land_marktscan+ '#home_bestellen');
      }
    }