Leiderman, R. (1990). The telephone book: How to find get,keep and develop customers. McGraw Hill.
Dyfyniad Arddull ChicagoLeiderman, Robert. The Telephone Book: How to Find Get,keep and Develop Customers. London: McGraw Hill, 1990.
Dyfyniad MLALeiderman, Robert. The Telephone Book: How to Find Get,keep and Develop Customers. McGraw Hill, 1990.
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