Collaborative Concept Extraction from Documents. - Keiichi Nakata; Angi Voß; Marcus Juhnke; Thomas Kreifelts (PAKM, 1998)

Concept indexing. - Angi Voß; Keiichi Nakata; Marcus Juhnke (GROUP, 1999)

Concepts as handles for sharing knowledge from documents. - Angi Voß; Keiichi Nakata; Marcus Juhnke; Thomas Schardt (HCI (2), 1999)

Concept as Knowledge Handles in Collaborative Document Management. - Angi Voß; Keiichi Nakata; Marcus Juhnke (WETICE, 1999)