Ashworth J. Julie & Clark J. John. (1999). Stepping Stones 3. Harlow, Longman, 1999.
Cita Chicago (17th ed.)Ashworth J. Julie i Clark J. John. Stepping Stones 3. Harlow, Longman, 1999, 1999.
Cita MLA (9th ed.)Ashworth J. Julie i Clark J. John. Stepping Stones 3. Harlow, Longman, 1999, 1999.
Atenció: Aquestes cites poden no estar 100% correctes.