Beyer W.A. <br/><br/>
Sets,numbers and universes. 
Beyer W.A.; mycielski J. 
 -  1974 
<br/><br/><label>Standard No.: </label>125678 
<br/><br/><label>Source: </label> Textual 
<br/><br/><label>Dewey Class. No.: </label>Bx, L4