var win1Open = null
var win2Open = null
var win3Open = null
var win4Open = null

function openPopUp(windowURL, windowName) 
  { 
  var winHandle = window.open(windowURL,windowName,"toolbar=no, scrollbars=yes, resizable=yes")
  return winHandle
  } // open pop-up windows

function winClose()
  {    
  if(win1Open != null) win1Open.close() 
  } // close all open pop-up windows

function openPopUpWindow()
  {} // required by JavaScript & shows in status bar