edited by Vergilius Ferm
Philosophical Library, 1945
Buku Referensi
Geovanie, Jeffrie, author
Gramedia Pustaka Utama, 2013
Buku Teks
David Marquand; Ronald L. Nettler., editor
Blackwell Publisher, 2000
Buku Teks
Mary Bryden
Routledge, 2001
Buku Teks
Farrington, Karen, author
Chancellor Pres, 1998
Buku Referensi