University of Chicago. Industrial Relations Center. (1967). Exchange: Elementary school economics III (Field test ed.). Industrial Relations Center, University of Chicago.
Chicago-referens (17:e uppl.)University of Chicago. Industrial Relations Center. Exchange: Elementary School Economics III. Field test ed. Chicago: Industrial Relations Center, University of Chicago, 1967.
MLA-referens (8:e uppl.)University of Chicago. Industrial Relations Center. Exchange: Elementary School Economics III. Field test ed. Industrial Relations Center, University of Chicago, 1967.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.