var subWin;    

 function  openNewsWindow(){
    if (subWin==null || subWin.closed) {
       subWin=window.open("","subWindow", "scrollbars=yes,toolbar=no,statusbar=no,resizable=no,top=50,left=200,height=520, width=500");
   } 
     subWin.document.clear();
     subWin.focus();
  }

 function  openMetadataWindow(){
    if (subWin==null || subWin.closed) {
       subWin=window.open("","metadata", "scrollbars=yes,toolbar=no,statusbar=no,resizable=yes,top=5,left=300,height=480, width=600");
   } 
     subWin.document.clear();
     subWin.focus();
  }

 function  openCitationWindow(){
    if (subWin==null || subWin.closed) {
       subWin=window.open("","citation", "scrollbars=yes,toolbar=no,statusbar=no,resizable=yes,top=5,left=200,height=450, width=500");
   } 
     subWin.document.clear();
     subWin.focus();
  }

 function  openBrowseWindow(){
    if (subWin==null || subWin.closed) {
       subWin=window.open("","browse", "scrollbars=yes,toolbar=no,statusbar=no,resizable=yes,top=5,left=200,height=450, width=500");
   } 
     subWin.document.clear();
     subWin.focus();
  }

  function  openSubWindow(){
       if (subWin==null || subWin.closed) {
           subWin=window.open("","subWindow", "scrollbars=yes,resizable=yes,top=50,left=200,height=480, width=500");
       } 
       subWin.document.clear(); //location.href="about:blank";     
       subWin.focus();
  }

  /* -------------------------------------------------------
          Pop up a window in the center of the screen.
     ------------------------------------------------------- */
  function popWindowCenter(mypage, myname, w, h, scroll) {
	var winl = (screen.width - w) / 2;
	var wint = (screen.height - h) / 2;
	winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars='+scroll+',resizable'
	win = window.open(mypage, myname, winprops)
	if (parseInt(navigator.appVersion) >= 4) { win.window.focus(); }
  }