Crystal, David, 1941-
Cambridge University Press, 1995
Buku Referensi
Crystal, David, 1941-
Cambridge University Press, 1997
Buku Referensi
Crystal, David, 1941-
Cambridge University Press, 1991
Buku Referensi
Crystal, David, 1941-
Nuansa Cendekia, 2015
Buku Referensi
edited by Adrian Friday, David S. Ingram
Cambridge University Press, 1985
Buku Referensi