Novosti Press Agency Pub. House, 1976
Buku Teks
edited by Helmut Arntz
Press and Information Office of the Federal Government, 1961
Buku Teks
Chudal, Alaka Atreya, author
Oxford University Press, 2016
eBooks
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 1977
UI - Tesis (Membership)
Rangkuti-Hasibuan, Sofia, author
Dian Rakyat, 1992
Buku Teks