The Group, 1994
Buku Teks
Nindya Putri Ferina, author
Universitas Indonesia, 2019
UI - Skripsi (Membership)
Ranaweera, A. Mahinda, author
IKIP Semarang Press , 1994
Buku Teks
Hicks, Ursula K., author
Clarendon Press, 1961
Buku Teks
Muhammad Gilang Madiantara, author
2016
UI - Skripsi (Membership)