Gaya APA
Principles Of Economic. (1989).
Amerika:
Prentice-Hall.
Gaya Chicago
Principles Of Economic.
Ed. 4.
Amerika:
Prentice-Hall,
1989.
.
Gaya MLA
Principles Of Economic.
Ed. 4.
Amerika:
Prentice-Hall,
1989.
.
Gaya Turabian
Principles Of Economic.
Amerika:
Prentice-Hall,
1989.
.