function popupMap(GridRef) {
            window.open('http://www.multimap.com/map/places.cgi?client=europe&quicksearch=' + GridRef + '&scale=25000','popupMap','width=826,height=548,screenX=50,screenY=50,top=50,left=50,location=no,menubar=no,resizable=yes,scrollbars=no,status=yes,toolbar=no');
}