Allen, Widdowson, author
[publisher not identified], [date of publication not identified]
Buku Teks
Oxford University Press, 1978
Buku Teks
2008
Majalah, Jurnal, Buletin
edited by Elaine Treharne ... [etal]
Humanities Press, 1992
Buku Teks
Amsterdam : Swets & Zeitlinger
Majalah, Jurnal, Buletin