Singh, Jasprit
McGraw-Hill, 1995
Buku Teks
edited by Marian A. Herman
John Wiley & Sons, 1980
Buku Teks
Kressel, Henry
Academic Press, 1977
Buku Teks
Thompson, G.H.B.
John Wiley & Sons, 1980
Buku Teks
Nelson, Richard R.
American Enterprise Institute for Public Policy Research, 1984
Buku Teks