Buckley, E. A. (1961). How to increase sales with letters. McGraw Hill.
Chicago Edition CitationBuckley, Earle A. How to Increase Sales with Letters. McGraw Hill, 1961.
ציטוט MLABuckley, Earle A. How to Increase Sales with Letters. McGraw Hill, 1961.
אזהרה: ציטוטים אלה לעיתים לא מדויקים ב 100%.