Asimov, Isaac. <br/><br/>
How we found out about Outer Space /  

 - 1st ed /  
 - Essex :   Longman Group Ltd.. 
 - p.55 :  
<br/><br/><label>ISBN: </label>0-582-39147-4 
<br/><br/><label>Subjects--Topical Terms: </label><br/>outer Space
<br/><br/><label>Dewey Class. No.: </label>B97  / L7