Mockor, Jiri. <br/><br/>
Groups of Divisibility / 
Jiri Mockor. 
 - Dordrecht :  Prague :  D. Reidel Publishing Company ;  SNL-Publishers of Technical Literature,  1983. 
 - 184 s. :  il. ;  22 cm. 
 - Mathematics and Its Applications. East European Series .
 - Mathematics and Its Applications. East European Series .
<br/><br/>bibliogr. 
<br/><br/><label>ISBN: </label>9027715394 
<br/><br/><label>Uniwersalna Klasyfikacja Dziesiętna: </label> 512.5