Laily Suharlina Mahalli, author
Fakultas Eknonomi dan Bisnis Universitas Indonesia, 2000
UI - Tesis (Membership)
Watt, Kenneth E.F., 1929-
Allyn and Bacon, 1982
Buku Teks
Allen, James, author
The Benjamin Cumming Pub. Co., 1987
Buku Teks
Ellis, Peter, 1969-, author
Learning Matters, 2019
Buku Teks
Kempson, Ruth M., author
Blackwell , 2001
Buku Teks