function popup (href, width, height){	

	var windowHeight = window.innerHeight || document.body.offsetHeight;
	var windowWidth = window.innerWidth || document.body.offsetWidth;

  var top = Math.ceil((windowHeight/2) - (height/2));
  var left = Math.ceil((windowWidth/2) - (width/2));
	
	if(top>400) top = 200;

  newWindow = open(href ,'window' , 'width='+width+', height='+height+', top='+top+', left='+left+', menubar=no, status=no, locationbar=no, scrollbars=yes, resizeable=no');
	
}