The New Encyclopaedia Britannica : volume 1, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 11, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 4, micropaedia ready reference
Encyclopaedia Britannica Inc., 1988
 Buku Referensi
The New Encyclopaedia Britannica : volume 6, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
The New Encyclopaedia Britannica : volume 5, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
 Buku Referensi