Johnson, Philip I.
The ada primer: an introduciton to the ada language system
McGraw-Hill, 1985
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Cook, Vivian
Second language learning and language teaching
ARNOLD, 2001
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Hankes, Elmer Joseph
A universal second language
Hankes Foundation, 1992
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the Development of second language proficiency
Birgit Harley...[et al.], edited
Cambridge University Press , 1990
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Saville-Troike, Muriel, 1936-
Introducing second language acquisition
Cambridge University Press , 2006
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