edited by Muriel Albers Bittel, Lester Robert Bittel and Jackson Eugene Ramsey
Grolier International, 1995
Buku Referensi
Jones, John G.
Alexander Hamilton Institute, 1961
Buku Teks
Still, Richard R.
Prentice Hall International, 1988
Buku Teks
Hombur, Christian, 1962-
[Springer, ], 2012
eBooks
Storholm, Gordon R.
Prentice-Hall, 1982
Buku Teks