edited by John Ferguson and Kitty Chisholm
Open University, 1988
Buku Referensi
Anastasiou, Michaelangelo, author
Routledge, 2020
Buku Teks SO
Hood, Hugh
Oberon Press, 1977
Buku Teks
Hood, Hugh
General Publishing Co., 1980
Buku Teks
Burke
Avon Book Division, 1965
Buku Teks