Dyfyniad APA

Buckley, E. A. (1961). How to increase sales with letters. McGraw Hill.

Dyfyniad Arddull Chicago

Buckley, Earle A. How to Increase Sales with Letters. McGraw Hill, 1961.

Dyfyniad MLA

Buckley, Earle A. How to Increase Sales with Letters. McGraw Hill, 1961.

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