Weymar, Paul
A. Deutsch, 1957
Buku Teks SO
Deddy Wibowo Lesmana
Fakultas Ilmu Pengetahuan Budaya Universitas Indonesia, 1979
UI - Skripsi Membership
Naura Azka Hanifa
The Press and Information Office of the Federal Government, 1961
Buku Teks SO
Press and Information Office of the Federal Government, 1961
Buku Teks SO
Barton, Greg
Saufa, IRCiSoD, LKIS, 2016
Buku Teks SO