On the track of discovery / 
translated by David Skvirsky. 
 - Moscow :    Progress Publishers,  1967. 
 - 238 p. :  ill. ;  21 cm. 
 - Series 3. .
<br/><br/>324  324 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Science -- Miscellanea.
<br/><br/><label>Dewey Class. No.: </label>910 / P943o