A method to produce dried single-layer or multi-layer paper is disclosed. The method comprises, for a single-layer paper, preparing and spraying a partially dehydrated first fibrous web with a spray solution or suspension to give a sprayed partially dehydrated first fibrous web, and dehydrating the sprayed partially dehydrated first fibrous web by applying heat to form a dried single-layer paper; or, for a multi-layer paper, preparing and spraying a partially dehydrated layer compound with a spray solution or suspension to form a sprayed layer compound, and dehydrating the sprayed layer compound by applying heat to form a dried multi-layer paper. The spray solution or suspension comprises water and at least one water-soluble polymer P, which is obtained by polymerizing: (i) a monomer of formula H2CCHNHC(0)R1, where R1 is H or C1-C6- alkyl; and (ii) one or more ethylenically unsaturated monomers different from monomer (i).