Diakonoff, Igor M.
Cambridge University Press, 1999
Buku Teks
Heller, Agnes
Routledge & Kegan Paul, 1982
Buku Teks
Croce, Benedetto
George Allen and Unwin, 1949
Buku Teks
Croce, Benedetto
Meridian, 1955
Buku Teks
Cohen, Morris R.
Open Court, 1961
Buku Teks