University of Chicago. Industrial Relations Center. (1967). Exchange: Elementary school economics III (Field test ed.). Industrial Relations Center, University of Chicago.
Chicago-viite (17. p.)University of Chicago. Industrial Relations Center. Exchange: Elementary School Economics III. Field test ed. Chicago: Industrial Relations Center, University of Chicago, 1967.
MLA-viite (8. p.)University of Chicago. Industrial Relations Center. Exchange: Elementary School Economics III. Field test ed. Industrial Relations Center, University of Chicago, 1967.
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