Cita APA

Open University Course Team. (1976). Approximation I and II.Units 9 and 10 (4th ed.). Open uty press.

Chicago Edition Citation

Open University Course Team. Approximation I and II.Units 9 and 10. 4th ed. Open uty press, 1976.

Cita MLA

Open University Course Team. Approximation I and II.Units 9 and 10. 4th ed. Open uty press, 1976.