Zhen Ru Dai Jens Grabowski Helmut Neukirchen T911IMED TTCN-3 Based Graphical Real-Time Test Specification. 110-127 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2644&spage=110 2003 conf/pts/2003 TestCom db/conf/pts/testcom2003.html#DaiGN03