Dyfyniad APA

WIERSEMA FRED. (1998). CUSTOMER SERVICE. HARPER COLLINS PUBLISHERS.

Dyfyniad Arddull Chicago

WIERSEMA FRED. CUSTOMER SERVICE. NEW YORK: HARPER COLLINS PUBLISHERS, 1998.

Dyfyniad MLA

WIERSEMA FRED. CUSTOMER SERVICE. HARPER COLLINS PUBLISHERS, 1998.

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