Department Of social Affairs, 1950
Buku Teks
Milosz, Czeslaw, author
Yayasan Obor Indonesia, 1986
Buku Teks
Isna Alfiathi, author
Universitas Indonesia, 2009
UI - Skripsi (Open)
Dewey, John, author
Saksama, 1953
Buku Teks
The Asia Foundation, 2003
Buku Teks