Masataka Takamura Yoshihide Igarashi Group Mutual Exclusion Algorithms Based on Ticket Orders. 232-241 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2697&spage=232 2003 conf/cocoon/2003 COCOON db/conf/cocoon/cocoon2003.html#TakamuraI03