Epstein, T. Scarlett
Manchester University Press , 1962
Buku Teks
Veit, Lawrence A.
McGraw-Hill, 1976
Buku Teks
Pearson Longman, 2008
Buku Teks
edited by C. Steven LaRue
Fitzroy Dearborn Publishers, 1997
Buku Referensi
Rosen, George
University California Press, 1966
Buku Teks