BB	ALEXANDER, L. G.: Longman English Grammar Practice. Longman. 1990
BB	BEIGDEBER ATIENZA, F.: Diccionario Politécnico de las Lenguas Española e Inglesa. Díaz de Atienza
BB	Dudley-Evans, Tony. Nucleus, english for science and technology engineering / Tony Dudley-Evans, Tim Smart, John Wall. London : Longman Group, 1978
BB	EASTWOOD, John: Oxford Practice Grammar. Oxford University Press. 1992
BB	Engineering. Civil and Mechanical Engineering. English Language Services, Inc. Collier Macmillan Publishers.
BB	IBOTTSON, Mark. English for Engineering/IBOTTSON, Mark. Cambridge University Press.2008