Cassidy, D. (1993). It`s when you sell that counts. Vision Books.
Cita Chicago (17th ed.)Cassidy, Donald. It`s When You Sell That Counts. New Delhi: Vision Books, 1993.
Cita MLA (9th ed.)Cassidy, Donald. It`s When You Sell That Counts. Vision Books, 1993.
Atenció: Aquestes cites poden no estar 100% correctes.