TY  - BOOK
AU  - Gude,Kathy
AU  - Duckworth,Michael
TI  - Proficiency masterclass
SN  - 0194328236 (student's book)
U1  - 428 
PY  - 1999///-2000
CY  - Oxford
PB  - Oxford University Press
KW  - Ingles- Enseñanza
N1  - Student's book -- Teacher's book -- Workbook -- Workbook with answers
ER  -