Marking photographs

Has anyone any suggestions for writing on the verso of modern
photographs printed on resin coated paper?  At the moment, the
institution is using "Pigma Pens" but they are concerned about the
long term archival stability of them.  They find that soft pencil
smears and rubs off.  Marking the sleeve is not sufficient, as the
possibility always exists that they may become separated.  Are there
any suitable labels on the market that have been tested and found to
have stable adhesive.  Thanks,

Julia M. Landry
Council of Nova Scotia Archives

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                  Conservation DistList Instance 9:27
                Distributed: Tuesday, September 19, 1995
                        Message Id: cdl-9-27-011
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