XPath Typing Using a Modal Logic with Converse for Finite Trees.

Pierre Genevès Nabil Layaïda Alan Schmitt XPath Typing Using a Modal Logic with Converse for Finite Trees. 61-72 2007 conf/planX/2007 PLAN-X http://www.plan-x-2007.org/plan-x-2007.pdf db/conf/planX/planX2007.html#GenevesLS07