Beveridge, William Henry Beveridge, Baron, 1879-1963, author
George Allen and Unwin, 1949
Buku Teks
Johnson, Norman, author
Martin Robertson, 1981
Buku Teks
Busyra Azheri, author
RajaGrafindo Persada, 2012
Buku Teks
DeRosa, Thomas F., author
John Wiley & Sons, 2009
Buku Teks
Dunn, Dana S., author
Wiley-Blackwell, 2009
Buku Teks