/*
 * This script defines the object nieuwWindow
 * it defines the function newWindow(linkname), which opens nieuwWindow with the given link.
 * it defines closeWindow() which closes nieuwWindow if that is open.  
 */
 nieuwWindow = null;
 function newWindow(linkname){
   var nieuwWindow = window.open(linkname,"linkname","toolbar,scrollbars,resizable,width=800,height=600");
   nieuwWindow.focus()
 }
 function closeWindow(){if(nieuwWindow && !nieuwWindow.closed){nieuwWindow.close()}}