Douglas, L. V. (1973). Teaching business subjects (3rd. ed.). Prentice Hall.
Chicago Edition CitationDouglas, Llyod V. Teaching Business Subjects. 3rd. ed. New Jersy: Prentice Hall, 1973.
Cita MLADouglas, Llyod V. Teaching Business Subjects. 3rd. ed. Prentice Hall, 1973.
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