Widy Hartono
2019
UI - Tesis (Membership)
Bennington, James L. (James Lynne), 1935-
W.B. Saunders, 1984
Buku Referensi
Fadly Persi
Universitas Indonesia, 2000
UI - Tesis (Membership)
Estridge, Barbara H.
Delmar Cengage Learning, 2012
Buku Teks
Johnson, Catherine W.
Thomson , 2003
Buku Teks