function show_inputs(id_element) {
  if (document.getElementById(id_element).style.visibility == 'hidden')
  document.getElementById(id_element).style.visibility = 'visible';
  else
  document.getElementById(id_element).style.visibility = 'hidden';
  
  if(id_element=='address2' && document.getElementById('name2').value =='')
  document.getElementById('name2').value = document.getElementById('name').value + ' ' + document.getElementById('surname').value;
  
  return false;	
	}
	
 function isNumberKey(evt)
      {
         var charCode = (evt.which) ? evt.which : event.keyCode
         if (charCode > 31 && (charCode < 48 || charCode > 57))
            return false;

         return true;
      }