Commons, John R.
Macmillan, 1956
Buku Teks
Bach, George Leland, author
Prentice-Hall, 1968
Buku Teks
Bach, George Leland, author
Prentice-Hall, 1960
Buku Teks
Bach, George Leland, author
Prentice-Hall, 1956
Buku Teks
Harrod, R.F., author
Macmillan, 1956
Buku Teks