Cleaning embossed leather wall coverings

A query on behalf of a friend not on the list.  What is an appropriate
solvent for cleaning embossed leather 'wallpaper'? The leather has
cigarette and cigar staining, and general soiling. The wall covering
dates from the early 1920s and is coloured blue, green and red.  Any
suggestions would be much appreciated.

Vicki Heikell
National Library of New Zealand

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                  Conservation DistList Instance 8:16
                 Distributed: Thursday, August 25, 1994
                        Message Id: cdl-8-16-013
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