The New Encyclopaedia Britannica : volume 4
Encyclopaedia Britannica Inc., 1978
 Buku Referensi
The New Encyclopaedia Britannica : volume 4
Encyclopaedia Britannica Inc., 1988
 Buku Referensi
The New Encyclopaedia Britannica : volume 4, micropaedia ready reference
Encyclopaedia Britannica Inc., 2002
 Buku Referensi
The New Encyclopaedia Britannica : volume 4, micropaedia ready reference
Encyclopaedia Britannica Inc., 1988
 Buku Referensi
Encyclopaedia Britannica : volume 4
Encyclopaedia Britannica Inc., 1967
 Buku Referensi