Campbell, George L.
Concise compendium of the worlds languages
Routledge, 1998
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Katzner, Kenneth
The languages of the world
Routledge, 1995
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The World's major languages
edited by Bernard Comrie
Oxford University Press, 1987
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The World's major languages
edited by Bernard Comrie
Routledge, 1991
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Atlas of the world's languages
general editors, Christopher Moseley and R.E. Asher; section editors Mary Tait ... [and others]
Routledge, New York Routledge Reference 1994
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