Alessandra Cavarra Juliana Küster Filipe Formalizing Liveness-Enriched Sequence Diagrams Using ASMs. 62-77 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3052&spage=62 2004 conf/asm/2004 Abstract State Machines db/conf/asm/asm2004.html#CavarraK04