Gaya APA
Skill With People. (2009).
Jakarta:
Gramedia Pustaka Utama.
Gaya Chicago
Skill With People.
.
Jakarta:
Gramedia Pustaka Utama,
2009.
Text.
Gaya MLA
Skill With People.
.
Jakarta:
Gramedia Pustaka Utama,
2009.
Text.
Gaya Turabian
Skill With People.
Jakarta:
Gramedia Pustaka Utama,
2009.
Print.