Radford, Albert E., author
Harper and Row, 1986
Buku Teks
edited by P.B. Kirti
CRC Press Taylor & Francis Group, 2008
Buku Referensi
USA : Macmillan, 1996,
Buku Referensi
prepared under the editorial supervision of In Plain English, Inc.
Macmillan, 1996
Buku Referensi
Borland, [19?-]
Buku Teks