Billings, H. (1990). Magic and Hypersystems: A New Orderliness for Libraries.
Cita Chicago Style (17a ed.)Billings, Harold. Magic and Hypersystems: A New Orderliness for Libraries. 1990.
Cita MLA (9a ed.)Billings, Harold. Magic and Hypersystems: A New Orderliness for Libraries. 1990.
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