CAMPBELL, M. (1991). Satu, dua, tiga [1-2-3] 2.4 The Complete Reference / Mary Campbell. McGraw-Hill.
Chicago-viite (17. p.)CAMPBELL, Mary. Satu, Dua, Tiga [1-2-3] 2.4 The Complete Reference / Mary Campbell. McGraw-Hill, 1991.
MLA-viite (8. p.)CAMPBELL, Mary. Satu, Dua, Tiga [1-2-3] 2.4 The Complete Reference / Mary Campbell. McGraw-Hill, 1991.
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