Clark, Giles, author
Routledge, 1996
Buku Referensi
Clark, Giles, author
Routledge, 1996
Buku Referensi
George Allen and Unwin, 1984
Buku Teks
Clark, Giles, author
Routledge , 1996
Buku Teks
Hajnal, Peter I., author
New York : Oceana Publications, 1978,
Buku Referensi