Marking CDs

A music librarian asks what to use to mark CDs? They currently use a pen
with "permanent ink" using the bare minimum of marks on the center ring.
Will it damage the disc?  Should she use a pen from University Products
called Black Actinic described as chemically stable and non reactive
with paper and other materials? What are all you folks using???

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                  Conservation DistList Instance 5:34
                 Distributed: Sunday, December 22, 1991
                        Message Id: cdl-5-34-006
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