Ferguson, John H.
The American system of government
McGraw-Hill, 1947
Buku Teks
Ferguson, John H.
The American system of government
McGraw-Hill, 1981
Buku Teks
Ferguson, John H.
The American system of government
McGraw-Hill, 1956
Buku Teks
Ferguson, John H.
The American system of government
McGraw-Hill, 1965
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Griffith, Ernest S.
Congress Its contemporary role/ Ernest S. Griffith
New York University press, 1956
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