BC	Alexander, L.G.. Longman English grammar practice / L.G. Alexander . London ; New York : Longman, 1990
BC	Azar, Betty Schrampfer. Understanding and using english grammar / Betty Schrampfer Azar . 2nd ed. New Jersey : Prentice Hall Regents, 1989
BC	Beigbeder Atienza, Federico. Diccionario politécnico de las lenguas española e inglesa = Polytechnic dictionary of Spanish and English languages / F. Beigbeder Atienza . 2a. ed. Madrid : Díaz de Santos, S.A., 1997
BC	Bolton, David. English grammar in steps / english grammar presented, explained and practised in context by David Bolton and Noel Goodey . [1ª ed.] London : Richmond, D. L. 2004
BC	Collins Cobuild ... English language dictionary / developed and compiled in the English Department at the University of Birmingham as part of a language research project commissioned by Collins Publishers . [1st ed., 6th repr.] London ; Glasgow : Collins ; Stuttgart : Klett, 1992
BC	Collins Cobuild ... English language dictionary / developed and compiled in the English Department at the University of Birmingham as part of a language research project commissioned by Collins Publishers . [1st ed., 6th repr.] London ; Glasgow : Collins ; Stuttgart : Klett, 1992
BC	Eastwood, John. Oxford practice grammar : with answers / John Eastwood . [1st ed., 2nd. repr.] Oxford : Oxford University Press, 1992
BC	Murphy, Raymond. English grammar in use : a self-study reference and practice book for intermediate students : with answers / Raymond Murphy . 1st. pub., 16th printing Cambridge : University Press, 1992

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