Proficiency masterclass /
Kathy Gude, Michael Duckworth.
- Oxford : Oxford University Press, 1999-2000.
- 217- 88 p. : ill. ; 28 x 22 cm. Ejercicios con respuestas.
Student's book -- Teacher's book -- Workbook -- Workbook with answers
0194328236 (student's book) 0194328325 (workbook with answers)