Removal of crayon markings from documents

We recently encountered unwanted crayon markings on several pages of an
1875 historical atlas and were unsure how to proceed with their removal.
Since the crayon has been on the paper for an extended period and has
produced a greasy shadow image of itself on the reverse, we were
hesitant to do any treatment whatsoever for fear it might aggravate the
documents' condition.  Could someone please advise what would be best in
a situation such as this.  Thank you.

Frederick N. Honneffer
Document Conservator
C.A.C.
Bowling Green State University

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                  Conservation DistList Instance 8:26
                Distributed: Wednesday, October 12, 1994
                        Message Id: cdl-8-26-008
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