Alain Cournier Ajoy Kumar Datta Franck Petit Vincent Villain Optimal snap-stabilizing PIF algorithms in un-oriented trees. 185-200 2005 14 J. High Speed Networks 2 http://iospress.metapress.com/openurl.asp?genre=article&issn=0926-6801&volume=14&issue=2&spage=185 db/journals/jhsn/jhsn14.html#CournierDPV05