Korpela, Antti, et al. “Piloting Wet Tensile Strength Development of Polyamide-Amine-Epichlorohydrin Wet Strengthened Nordic Bleached Softwood Pulp Paper by Alkyl Ketene Dimer Internal Sizing”. BioResources, vol. 17, no. 4, Nov. 2022, pp. 6970-82, https://ojs.bioresources.com/index.php/BRJ/article/view/22144.