H. Schuldt, C. Schuler, G. Alonso, and H. Schek. Enterprise-wide and Cross-enterprise Workflow Management, volume 24 of CEUR Workshop Proceedings, page 65-71. CEUR-WS.org, (1999)
H. Schuldt, A. Popovici, and H. Schek. Enterprise-wide and Cross-enterprise Workflow Management, volume 24 of CEUR Workshop Proceedings, page 10-17. CEUR-WS.org, (1999)
H. Schek. SIGIR, page 55-70. Cambridge University Press, on behalf of the British Computer Society (copyright by British Informatics Society Ltd, a subsidiary of the British Computer Society), (1984)