Souter, Gerry
Andre Deutsch, 2015
Buku Referensi
editor in chief, Stanley I. Kutler
Charles Scribner's Sons, 1996
Buku Referensi
Bodard, Lucien
Atlantic Monthly Press Book, 1967
Buku Teks
Moyar, Mark
Cambridge University Press, 2006
Buku Teks
Knoebl, Kuno
Frederick A. Praeger , 1967
Buku Teks