Craven, R. (2002). Customer is king: How to exceed their expectations. Virgin Books.
Citazione stile Chigago Style (17a edizione)Craven, Robert. Customer Is King: How to Exceed Their Expectations. London: Virgin Books, 2002.
Citatione MLA (9a ed.)Craven, Robert. Customer Is King: How to Exceed Their Expectations. Virgin Books, 2002.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.