Spillard, P. (1975). Sales promotion (2nd ed.). Business books.
Dyfyniad Arddull ChicagoSpillard, P. Sales Promotion. 2nd ed. Business books, 1975.
Dyfyniad MLASpillard, P. Sales Promotion. 2nd ed. Business books, 1975.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.