DUNCAN TOM. (1992). MARKETING STUDY GUIDE BY CONSTANTINE G: PETRIDES & HOWARD R BUDNER. PRENTICE -HALL INTERNATIONAL; INC.
Lua i Stíl Chicago (17ú heag.)DUNCAN TOM. MARKETING STUDY GUIDE BY CONSTANTINE G: PETRIDES & HOWARD R BUDNER. NEW JERSEY; U.S.A: PRENTICE -HALL INTERNATIONAL; INC, 1992.
Lua MLA (9ú heag.)DUNCAN TOM. MARKETING STUDY GUIDE BY CONSTANTINE G: PETRIDES & HOWARD R BUDNER. PRENTICE -HALL INTERNATIONAL; INC, 1992.
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