Murdock, George Peter, author
McGraw-Hill, 1959
Buku Teks
Azim A. Nanji, editor
Gale Research, 1996
Buku Referensi
Brockelmann, Carl, author
Routledge & Kegan Paul , 1950
Buku Teks
Morton, A.L., author
Victor Gollancz, 1938
Buku Teks
Churchill, Winston, Sir, 1874-1965, author
Wings Books, 1994
Buku Teks