The Encyclopedia Americana : volume 9
Americana Corporation, 1977
 Buku Referensi
The Encyclopedia Americana : volume 9
Americana Corporation, 1964
 Buku Referensi
Collier's encyclopedia : volume 9
Macmillan Educational Company, 1990
 Buku Referensi
Grolier family encyclopedia : volume 9
Grolier Incorporated, 1995
 Buku Referensi
The World book encyclopedia : volume 9
World Book, 1985
 Buku Referensi