NCC Publications, 1984
Buku Referensi
Buchanan, Bill, author
Kluwer Academic Publishers, 1999
Buku Referensi
West, Brian G., author
Oxford Road, 1986
Buku Teks
West, Brian G., author
Oxford Road, 1986
Buku Teks
West, Brian G., author
Oxford Road, 1986
Buku Teks