Paul Dourish Jim Holmes Allan MacLean Pernille Marqvardsen Alex Zbyslaw Freeflow: Mediating Between Representation and Action in Workflow Systems. 190-198 1996 CSCW http://doi.acm.org/10.1145/240080.240252 db/conf/cscw/cscw1996.html#DourishHMMZ96