Gaya APA
Search Engine Marketing. (2009).
New York:
[s.n.].
Gaya Chicago
Search Engine Marketing.
.
New York:
[s.n.],
2009.
Text.
Gaya MLA
Search Engine Marketing.
.
New York:
[s.n.],
2009.
Text.
Gaya Turabian
Search Engine Marketing.
New York:
[s.n.],
2009.
Print.