Segal, Louis, author
Frederick A. Praeger, 1959
Buku Referensi
Texnika, 1993
Buku Referensi
edited by Colin Howlett
Oxford University Press, 1996
Buku Referensi
Wheeler, Marcus, author
Glarendon Press, 1984
Buku Referensi
Shtevnfeldt, E., author
Progress, [date of publication not identified]
Buku Referensi