The New Encyclopaedia Britannica : volume 11, micropaedia ready reference
Encyclopaedia Britannica Inc., 2002
 Buku Referensi
The New Encyclopaedia Britannica : volume 2, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 7, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 10, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 8, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi