The astronomical almanac for the year 1997. 

 -- Washington :   U.S. Government Printing Office ; London,   1996 
 - ix, pág. var. 
<br/><br/>ISBN 0-11-886505-6 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomía<br/>Efemérides
<br/><br/><label>Universal Decimal Class. No.: </label>521(059.3)