Shtokalo, I Z <br/><br/>
Linear differential equations with variable coefficients: criteria of stability and unstability of their solutions 

 - Delhi  Hindustan Publishing  1961 
 - vii,100 p. 
<br/><br/><label>ISBN: </label> RS40 
<br/><br/><label>Dewey Class. No.: </label>515.35 S88L