The Encyclopedia Americana : volume 18
Grolier, 1994
Buku Referensi
The Encyclopedia Americana : volume 18
Americana Corporation, 1977
Buku Referensi
Collier's encyclopedia : volume 18
Macmillan Educational Company, 1990
Buku Referensi
Grolier family encyclopedia : volume 18
Grolier Incorporated, 1995
Buku Referensi
The World book encyclopedia : volume 18
World Book, 1984
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