Gaya APA
Research Design. (2002).
London:
New Delhi Sage.
Gaya Chicago
Research Design.
.
London:
New Delhi Sage,
2002.
Buku.
Gaya MLA
Research Design.
.
London:
New Delhi Sage,
2002.
Buku.
Gaya Turabian
Research Design.
London:
New Delhi Sage,
2002.
Buku.