Dieterich, Thomas G.
Center for Applied Linguistics, 1979
Buku Teks
Geoffrey, Leech N., author
Longmans, 1993
Buku Teks
Thomas, Joe G.
Houghton Miffiln, 1990
Buku Teks
Low, Ona, author
Edward Arnold, 1986
Buku Teks
Stone, Linton
Macmillan, 1967
Buku Teks