Brixey, John C., author
Holt, Rinehart and winston, 1954
Buku Teks
Marcela Prahastuti Krisnanda, author
Fakultas Psikologi Universitas Indonesia, 2018
UI - Skripsi (Membership)
Artikel Jurnal
Lueck, William R.
University, 1932
Buku Teks
Alvin Adelino, author
2017
UI - Skripsi (Membership)