The Zelcor book: an electronic knowledge book for the cascading use of biorefinery recalcitrant side streams into high added-value biobased products and fine chemicals The European Zelcor project (https://cordis.europa.eu/project/id/720303/fr) combines several scientific, technical competencies and know-how, as well as industrial expertises, for the valorisation of biorefineries by-products that are rich in lignins and humins. Considering the complexity and diversity of the scientific and technical fields relative to lignins and humins structure, to their extraction processes in biorefineries and to their valorisation into products, Zelcor has implemented a tool to organise the knowledge, for an efficient transmission and capitalisation within the consortium. A knowledge book was therefore constructed and delivered for this purpose. This hypermedia is specifically designed to facilitate the understanding of the biorefinery cascading strategy developed within Zelcor and of the major achievements. It is constituted by standardised graphical representations of concepts, validated by the Zelcor experts, and illustrating all achievements and results of the project.