The Encyclopedia Americana : volume 19
Grolier, 1994
 Buku Referensi
Grolier academic encyclopedia 19
London: Grolier International, 1991,
 Buku Referensi
Pandelwan (bendel 19)
[Publisher not identified], [Date of publication not identified]
 Naskah
The Encyclopedia Americana : volume 19
Americana Corporation, 1977
 Buku Referensi
The Encyclopedia Americana : volume 19
Americana Corporation, 1964
 Buku Referensi