TY  - BOOK
AU  - Murphy,Raymond
TI  - Essential grammar in use: a self-study reference and practice book for elementary students of english with answers 
U1  - 421.5 M978e 2007 
PY  - 2007///
CY  - Cambridge
PB  - Cambridge University Press, 
KW  - INGLES
KW  - GRAMATICA
KW  - PROBLEMAS, EJERCICIOS, ETC
KW  - TEXTO DE ESTUDIO
ER  -