function random_imglink(){
  var myimages=new Array()
  //specify random images below. You can have as many as you wish
  myimages[1]="e-banner/cbiot.gif"
  myimages[2]="e-banner/mirna.gif"
  myimages[3]="e-banner/cag.gif"
  
  //specify corresponding links below
  var imagelinks=new Array()
  imagelinks[1]="http://benthamscience.com/cbiot"
  imagelinks[2]="http://benthamscience.com/mirna"
  imagelinks[3]="http://benthamscience.com/cag"
  
  myimages[1]="e-banner/cbiot.gif"
  myimages[2]="e-banner/mirna.gif"
  myimages[3]="e-banner/cag.gif"
 
  //specify corresponding links below
  var imagelinks=new Array()
  imagelinks[1]="http://benthamscience.com/cbiot"
  imagelinks[2]="http://benthamscience.com/mirna" 
  imagelinks[3]="http://benthamscience.com/cag" 

  var ry=Math.floor(Math.random()*myimages.length)

  if (ry==0)
     ry=2
     document.write('<a href='+'"'+imagelinks[ry]+'"'+' onclick="window.open(this.href); return false;"><img src="'+myimages[ry]+'" border=0></a>')
}

  random_imglink()