DUNCKEL JACQUELINE. (1994). EFFECTIVE SPEAKING FOR BUSINESS SUCCESS MAKING CONFIDENT ... AND MORE. LANCER INTERNATIONAL.
Chicago-viite (17. p.)DUNCKEL JACQUELINE. EFFECTIVE SPEAKING FOR BUSINESS SUCCESS MAKING CONFIDENT ... AND MORE. INDIA CANADA USA: LANCER INTERNATIONAL, 1994.
MLA-viite (9. p.)DUNCKEL JACQUELINE. EFFECTIVE SPEAKING FOR BUSINESS SUCCESS MAKING CONFIDENT ... AND MORE. LANCER INTERNATIONAL, 1994.
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