Gaya APA
Humphrey, Edward. (1981).
The Americana Annual 1981 .
Canada:
Grolier International.
Gaya Chicago
Humphrey, Edward.
The Americana Annual 1981.
Canada:
Grolier International,
1981.
Buku.
Gaya MLA
Humphrey, Edward.
The Americana Annual 1981.
Canada:
Grolier International,
1981.
Buku.
Gaya Turabian
Humphrey, Edward.
The Americana Annual 1981.
Canada:
Grolier International,
1981.
Buku.