Rao, U R <br/><br/>
X-ray observation of Cen XR-4 and Nor XR-2.  [electronic resource] 

 -  Nature  Jan 1971 
 - 248-50 p.  digital 
<br/><br/> Publication Type: Journal Article 
<br/><br/><label>ISSN: </label>0028-0836 
<br/><br/><label>Standard No.: </label>10.1038/229248b0  doi