Gaya APA
Labor. (1958).
New York:
Mcgraw-Hill Book Company.
Gaya Chicago
Labor.
.
New York:
Mcgraw-Hill Book Company,
1958.
.
Gaya MLA
Labor.
.
New York:
Mcgraw-Hill Book Company,
1958.
.
Gaya Turabian
Labor.
New York:
Mcgraw-Hill Book Company,
1958.
.