document.write("<style type='text/css'> @import url('http://www.westlaw.aranzadi.es/banners_productos/css/banners.css'); </style>");


function advertisement() {
 // Array de imagenes
 var images = new Array;
    images[1] = "http://www.westlaw.aranzadi.es/banners_productos/westlaw/banner-enero1.gif";
    images[2] = "http://www.westlaw.aranzadi.es/banners_productos/westlaw/banner-enero2.gif";
    images[3] = "http://www.westlaw.aranzadi.es/banners_productos/westlaw/banner-enero3.gif";

 // Array de enlaces
 var links = new Array
 	links[1] = "http://www.aranzadiformacion.es";
    links[2] = "http://www.aranzadiformacion.es";
    links[3] = "http://www.aranzadiformacion.es";

// Array de enlaces
 var targets = new Array;
 targets[1] = "_blank";
 targets[2] = "_blank";
 targets[3] = "_blank";

// Array de enlaces
 var onclick = new Array;
   onclick[1] = "";
   onclick[2] = "";
   onclick[3] = "";

   var randomnumber = Math.floor(Math.random()*(images.length-1)) + 1;
    document.getElementById('advertisement').innerHTML = '<a onclick="' + onclick[randomnumber] + '"  href="' + links[randomnumber] + '" target="' + targets[randomnumber] + '" title=""><img src="' + images[randomnumber] + '" alt=""></a>';
	
}