Ur, Penny, author
Cambridge University Press, 1999
Buku Referensi
McArthur, Tom (Thomas Burns), author
Cambridge University Press, 1983
Buku Teks
Potapova, Nina F., author
Foreign Languages Publishing House, 1959
Buku Referensi
Potapova, Nina F., author
Foreign Languages Publishing House, 1959
Buku Teks
Ur, Penny, author
Cambridge University Press, 2006
Buku Teks