Gaya APA
Skill With People. (2005).
Jakarta:
Gramedia Pustaka Utama.
Gaya Chicago
Skill With People.
.
Jakarta:
Gramedia Pustaka Utama,
2005.
Buku.
Gaya MLA
Skill With People.
.
Jakarta:
Gramedia Pustaka Utama,
2005.
Buku.
Gaya Turabian
Skill With People.
Jakarta:
Gramedia Pustaka Utama,
2005.
Buku.