Happold, F.C.
Christophers, 1938
Buku Klasik
Braeman, John
Thomas Y Crowill, 1969
Buku Teks
Wolff, Robert Lee, author
Garland Publishing, 1981
Buku Referensi
Wolff, Robert Lee, author
Garland Publishing, 1985
Buku Referensi
Hudiningsih, author
1988
UI - Tesis (Membership)