The new Encyclopaedia Britannica in 30 volumes. 

 - Chicago :  [Encyclopaedia Britannica,  1975] 
 - 30 v. : ill. (part col.), maps ; 29 cm.  30 v. : ill. (part col.), maps ; 29 cm.  30 v. : ill. (part col.), maps ; 29 cm. 
<br/><br/> Supplements: Book of the year, 1975.