Ruvinsky, L. T. <br/><br/>
Activeness and self-education 

 - Moscow  Progress Publishers  1986 
 - 130p. 
<br/><br/><label>ISBN: </label> RS 3.75 
<br/><br/><label>Source: </label> RS 3.75 
<br/><br/><label>Dewey Class. No.: </label>370 RUV