Zulkarnain
Universitas Sumatera Utara. Faculty of Psychology, 2015
Artikel Jurnal
Zulkarnain
Universitas Sumatera Utara. Faculty of Psychology, 2015
Artikel Jurnal
Kharisma Priyo Nugroho
2002
UI - Tesis Membership
Milroy, Patrick
Ward Lock Book, 1994
Buku Referensi
edited by Freddie H. Fu, Steven B. Cohen
Slack Incorporated, 2008
Buku Teks SO