Reagents used to read underlying text in palimpsests

I have been looking for bibliographical references on the kind of
reagents that were used in the past to read the underlying text in
palimpsest manuscripts.

I have found some information in

    Wattenbach, W., 1896.
    Das Schriftwesen im Mittelalter, Leipzig: S. Hirzel, pp.311-317.

However, I was wondering if anyone has any written documentation or
know of any other book or scholarly article describing the type of
reagents used, especially--but not limited to--more recent
publications. Any help would be very much appreciated.

Alberto Campagnolo
Book and Paper Conservator
London, UK


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                  Conservation DistList Instance 26:17
                Distributed: Friday, September 14, 2012
                       Message Id: cdl-26-17-016
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