Ticoalu, Louna Carolina, author
1992
UI - Skripsi (Membership)
Julia Suleeman, author
Fakultas Psikologi Universitas Indonesia, 1993
UI - Laporan Penelitian
Artikel Jurnal
Fisher, Alec, author
Erlanga, 2009
Buku Teks
Najla, author
2001
UI - Skripsi (Membership)