Phillips, D.C., author
Stanford University Press, 1976
Buku Teks
Go, Julian, author
Oxford University Press, 2016
eBooks
Nadel, S.F. (Siegfried Frederick), author
The Free Press of Glencoe, 1964
Buku Teks
Allyn and Bacon, 1991
Buku Teks
Nadel, S.F. (Siegfried Frederick), author
Cohen & West, 1969
Buku Teks