The splitting of paper in order to stabilize it by interleaving is considered an essential technique of paper restoration. The sheet of paper which has to be divided is glued between a folded leaf of filter paper with a gelatine-glycerine glue. Then the cleaving proceeds from one corner until the upper and lower parts are separated. Missing parts are replenished before two parts are glued on the stable core of paper with a poly(vinyl acetate) glue. Finally the filter paperis removed.