Downey, Jake
Inggris EP Publishing 1982,
Buku Teks
Downey, Jake
Sterling Pub, 1982
Buku Teks
Amran Lee Abdullah, author
Sutrapadu (M) SDN. BHD., 2007
Buku Referensi
Mills, Roger
Bell & Hyman, 1985
Buku Teks
Mochamad Dani Sudaryono, author
2019
UI - Tesis (Membership)