Keller, Suzanne
Random House, 1968
Buku Teks
Meisel, James H.
Greenwood Press, 1958
Buku Teks
edited by Stanley Aronowitz and Michael Roberts
John Wiley & Sons, 2018
Buku Teks
Buchanan, James M.
Liberty Fund, 2000
Buku Referensi
Harain Surat Kabar Kompas, 2002
Buku Teks