Almanac for computers, 1989. 

 - Washington, D.C. :    National Almanac Office,    1989. 
 - v. ;    27 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Astronomy -- Periodicals.<br/> Nautical almanacs -- Data processing.<br/> Ethemerides -- Data processing -- Periodicals.