Burton R. Clark, Guy R. Neave, editors-in-cheif
Pergamon Press, 1992
Buku Referensi
editor, Burton R. Clark
Pergamon Press, 1992
Buku Referensi
Burton R. Clark, Guy R. Neave, editors-in-chief
Pergamon Press, 1992
Buku Referensi
UNESCO, 1978
Buku Teks
Her Majesty's Stationery Office, 1987
Buku Teks