Crystal, David, 1941-
Language death
Cambridge University Press, 2004
 Buku Teks SO
Language death / David Crystal
Cambridge University Press, 2004
 eBooks
Dalby, Andrew
Language in danger
A. Lane, 2002
 Buku Teks
Bloomfield, Leonard
Language
Holt, Rinehart and Winston, 1961
 Buku Teks SO
Austin, Peter K.
The Cambridge handbook of endangered languages
Cambridge University Press, 2011
 eBooks