Não informado. (2007). Marketing letters. Kluwer Academic Publishers.
Chicago (17e ed.) BronvermeldingNão informado. Marketing Letters. Dordrecht, Holanda: Kluwer Academic Publishers, 2007.
MLA (8e ed.) BronvermeldingNão informado. Marketing Letters. Kluwer Academic Publishers, 2007.
Let op: Deze citaties zijn niet altijd 100% accuraat.