Wolff, Robert Lee
Garland Publishing, 1985
Buku Referensi
compiled by Robert Lee Wolff
Garland Publishing, 1984
Buku Referensi
Karl, Frederick R.
Farrar, Straus and Giroux, 1964
Buku Teks
Ludlum, Robert
Grafton, 1991
Buku Teks
Brownings, Robert
Everymans Library, 1964
Buku Teks