George Braziller, 1962
Buku Teks
Moniz, Amanda B.
Oxford University Press, 2016
eBooks
Nash, Gary B.
Harvard University Press, 1979
Buku Teks
Bergstrom, Theodore C.
York McGraw-Hill , 2000
Buku Teks
Doyle, William
Oxford University Press , 1989
Buku Teks