Presidency of the Council of Ministers of the Republic of Italy, Information Service, 1962
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Schubert, Glendon A., Jr
University of Minnesota Press, 1956
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Pious, Richard M.
Basic Books, 1944
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Rossiter, Clinton, 1917-1970
American Library Association, 1960
Buku Teks SO
Longaker, Richard P.
Cornell University Press, 1962
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