Hartley, B. (1985). Streamline english: Departures, part A: units l-40 (9a. ed.). Oxford University Press.
Cita Chicago (17th ed.)Hartley, Bernard. Streamline English: Departures, Part A: Units L-40. 9a. ed. New York: Oxford University Press, 1985.
Cita MLA (9th ed.)Hartley, Bernard. Streamline English: Departures, Part A: Units L-40. 9a. ed. Oxford University Press, 1985.
Atenció: Aquestes cites poden no estar 100% correctes.