Dewey, Melvil
DDC 21 (Dewey Decimal Classification Edition 21) : Volume 4 Relative Index. Manual
New York : Forest Press, 1996,
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Dewey, Melvil
DDC 21 (Dewey Decimal Classification Edition 21) : Volume 3 Schedules 600-999
New York : Forest Press, 1996,
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Dewey, Melvil
DDC 21 (Dewey Decimal Classification Edition 21) : Volume 2 Schedules 000-599
Forest Press, 1996
 Buku Referensi
Sifton, Pat
Workbook for DDC 20 : Dewey Decimal Classification Edition 20
Canadian Library Association, 1989
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Davis, Sydney W.
DDC 20 workbook : a practical introduction to the Dewey Decimal Classification
Forest Press, 1992
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