Wehr, Hans, 1909-1981, author
Spoken Language Services, 1976
Buku Referensi
Aitchison, James, author
Cassell, 1994
Buku Teks
Halliday, M.A.K., author
Oxford University Press, 1989
Buku Teks
Foreign Languages Press, 1958
Buku Teks
Thatcher, G.W., author
Frederick Ungar, [Date of publication not identified]
Buku Teks