Oxford University Press, 1979
Buku Teks
edited and introduced by Andrew Shonfield and Stella Shaw
Heinemann Educational Books, 1972
Buku Teks
Arnold, Karl-Heinz
Panorama GDR, 1976
Buku Teks
Farley, John E., author
Prentice-Hall, 1987
Buku Teks
edited by Jonathan M. Harris and Neva R. Goodwin
Edward Elgar , 2003
Buku Teks