While the Web of Data, the Web of Documents and Natural Language Processing are well researched individual fields, approaches to combine all three are fragmented and not yet well aligned. This chapter analyzes current efforts in collaborative knowledge extraction to uncover connection points between the three fields. The special focus is on three prominent RDF data sets (DBpedia, LinkedGeo-Data and Wiktionary2RDF), which allow users to influence the knowledge extraction process by adding

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... crowd-sourced layer on top. The recently published NLP Interchange Format (NIF) provides a way to annotate textual resources on the Web through the assignment of URIs with fragment identifiers. We will show how this formalism can easily be extended to encompass new annotation layers and vocabularies.