Aharonian, F <br/><br/>
A low level of extragalactic background light as revealed by gamma-rays from blazars.  [electronic resource] 

 -  Nature  Apr 2006 
 - 1018-21 p.  digital 
<br/><br/> Publication Type: Journal Article 
<br/><br/><label>ISSN: </label>1476-4687 
<br/><br/><label>Standard No.: </label>10.1038/nature04680  doi