Steiner, Frederick R.
McGraw-Hill, 1999
Buku Referensi
University of British Columbia Press, 1982
Buku Teks
Sitorus, Balindo Dharma Bakti Samuel
2017
UI - Skripsi (Membership)
Nizhar Marizi
Program Pascasarjana Universitas Indonesia, 2005
UI - Tesis (Membership)
University of Illinois, 1960
Buku Teks