Sinaga, Martha
Habit Profesional
Gramedia, 2006
 Buku Teks
Covey, Stephen R.
The 8th habit : melampaui efektivitas, menggapai keagungan = The 8th habit
Gramedia, 2005
 Buku Teks SO
Covey, Stephen R.
The 8th habit : from effectiveness to greatness
Free Press, 2004
 Buku Teks
Toynbee, Arnold J.
Change and habit : the challenge of our tim
Oxford University Press, 1966
 Buku Teks SO
Journal of Population
The Demographic Institue FE-UI, 1995
 Majalah, Jurnal, Buletin