Gaya APA
Futures: a personal seminar. (1989).
New York:
.
Gaya Chicago
Futures: a personal seminar.
1.
New York:
,
1989.
Text.
Gaya MLA
Futures: a personal seminar.
1.
New York:
,
1989.
Text.
Gaya Turabian
Futures: a personal seminar.
New York:
,
1989.
Print.