Gaya APA
American principles and issues. (1961).
New York:
Holt Rinehart and Winston.
Gaya Chicago
American principles and issues.
.
New York:
Holt Rinehart and Winston,
1961.
Tesis.
Gaya MLA
American principles and issues.
.
New York:
Holt Rinehart and Winston,
1961.
Tesis.
Gaya Turabian
American principles and issues.
New York:
Holt Rinehart and Winston,
1961.
Tesis.