Abstract: A continuous paper strip is provided with a first plurality of transverse tear lines spaced apart from each other to divide the strip into a plurality of strip elements having a desired height. Each strip element is subdivided into a first and second part of different heights by a transverse folding line. The first part has a height "h+d", where "h" is the height of the invoice, bill or the like, and "d" is the width of the bands on which an adhesive is applied. The second part has a height "h+2d". Longitudinal slots are purchased at each side of the first part of each strip element each having a width equal to "d". On the main face of the strip and near the transverse folding line separating each strip element, an adhesive is applied on a band of a width substantially equal to "d", while at the opposite face of the strip and on the second part of each strip element an adhesive band is applied near the tear line.