1. Cause—Condition—Concession—contrast: Cognitive and Discourse Perspectives,2000
2. Concessives on different semantic levels: A typological perspective;Crevels,2000
3. Grammar in Interaction: Adverbial Clauses in American English Conversations;Ford,1993
4. Adverbial clauses in the languages of Europe;Hengeveld,1998
5. The meaning of converb constructions;König,1995