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The University of Chicago Press, 1986
Buku Teks
Boughey, Arthur S., author
McMillan Publisher, 1975
Buku Teks
Hawley, Amos H., author
The Ronald Press, 1950
Buku Teks
Program Pascasarjana Universitas Indonesia, 1994
Majalah, Jurnal, Buletin
Rogers, Edward S.
MacMillan Press , 1960
Buku Teks