Hartmut Ehrig Karsten Ehrig Annegret Habel Karl-Heinz Pennemann Theory of Constraints and Application Conditions: From Graphs to High-Level Structures. 135-166 2006 74 Fundam. Inform. 1 http://iospress.metapress.com/openurl.asp?genre=article&issn=0169-2968&volume=74&issue=1&spage=135 db/journals/fuin/fuin74.html#EhrigEHP06