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William Sloane Associates, 1950
Buku Teks
Clawson, Marion
Frederick A. Praeger, 1971
Buku Teks
Swanson, Charles R.
McGraw-Hill, 2003
Buku Teks
Swanson, Charles R.
McGraw-Hill, 2003
Multimedia
Berg, Bruce Lawrence, 1954-
McGraw-Hill Higher Education, 2008
Buku Teks