Proceedings of the XIII International conference on differential geometric methods in theoretical physics, Shumen, Bulgaria, 1984 
/ ed. by H.D. Doebner, T.D. Palev 
. - Singpore  : World Scientific, c1986
. - VIII-370 p.  ; 24 cm. 
<br/><br/>Bibliogr. pp.368-370. 
<br/><br/><label>ISBN: </label>9971500701 997150071X 
<br/><br/><label>Source: </label> Don 
<br/><br/><label>Universal Decimal Class. No.: </label>513.73