Mineral exports from Bolivia in 1933. 

 - New York-XXU :   The Bolivian Consulate,   1935. 
 - p. 18 
 - Bimestral 
 - Vol. V, no. 4 (May./Jun. 1935) 
 - Bolivia ;   no. 4 .
 - Estados Unidos.   The Bolivian Consulate. .