Lewis, N. (1993). Word Power Made Easy (3rd ed.). Bloomsbury Publishing Plc.
Cita Chicago (17th ed.)Lewis, Norman. Word Power Made Easy. 3rd ed. U.K: Bloomsbury Publishing Plc, 1993.
Cita MLA (9th ed.)Lewis, Norman. Word Power Made Easy. 3rd ed. Bloomsbury Publishing Plc, 1993.
Atenció: Aquestes cites poden no estar 100% correctes.