Trask, R.L.
Key concepts in language and linguistics
London, 1998
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Key Thinkers in linguistics and the Philosophy of language
Edinburgh, Edinburgh University Press, 2005
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Key thinkers in linguistics and the philosophy of language
edited by Siobhan Chapman
Oxford University Press, 2005
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Vernon, Mark
Bisnis: the key concepts = Business: the key concepts
RajaGrafindo Persada, 2011
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Key concepts in geography
edited by Sarah L. Holloway, Stephen P. Rice, Gill Valentine
Sage, 2003
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