National geographic Vol. 200, no.3 September 2001 How old is it? Solving the riddle of ages 

 - Washington, D.C.  National Geographic Society.  [date of publication not identified] 
 - v.  26cm 
<br/><br/> monthly 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geography -- Periodicals.