Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) Xueyu Du and Jiebing Li and Mikael E. Lindström,Modification of industrial softwood kraft lignin using Mannich reaction with and without phenolation pretreatment,Industrial Crops and Products,0926-6690,Elsevier BV,2014-01,52,,729-735,https://cir.nii.ac.jp/crid/1360857597726093568,https://doi.org/10.1016/j.indcrop.2013.11.035