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West Publishing Company, 1979
Buku Teks
Cook, Franklin Henry
Macmillan, 1951
Buku Teks
Willbrown, Steven L., author
Michie Law, 1995
Buku Teks
Taylor, Benjamin J., author
Prentice-Hall, 1987
Buku Teks
Committee Reports, 1974
Buku Teks