Preiss, S. (2009). NorthStar 5 (3rd edition.). Longman.
Cita Chicago (17th ed.)Preiss, Sherry. NorthStar 5. 3rd edition. White Plains, N.Y.: Longman, 2009.
Cita MLA (8th ed.)Preiss, Sherry. NorthStar 5. 3rd edition. Longman, 2009.
Atenció: Aquestes cites poden no estar 100% correctes.