Bloom, Gordon F.
Irwin , 1969
Buku Teks
Rolph, Earl R.
N.Y. The Ronald Press , 1961
Buku Teks
Maier, Norman R.F.
John Wiley & Sons, 1960
Buku Teks
Wendt, Paul F.
The University of California, 1966
Buku Teks
Cohn, Louis F.
John Wiley & Sons, 1982
Buku Teks