Gaya APA
Sagan, Carl. (1980).
Cosmos .
New York:
Ballantine.
Gaya Chicago
Sagan, Carl.
Cosmos.
New York:
Ballantine,
1980.
Text.
Gaya MLA
Sagan, Carl.
Cosmos.
New York:
Ballantine,
1980.
Text.
Gaya Turabian
Sagan, Carl.
Cosmos.
New York:
Ballantine,
1980.
Print.