Siti Rohmah Soekarba
Fakultas Ilmu Pengatahuan Budaya Universitas Indonesia, 1998
UI - Laporan Penelitian
Verlinden, Jay
Wadsworth/Thomson Learning, 2005
Buku Teks
Ennis, Robert Hugh
Prentice-Hall, 1996
Buku Teks
Paul, Richard W.
Prentice-Hall, 2002
Buku Teks
Moore, Brookee Noel
McGraw-Hill, 2015
Buku Teks