Yasunori Ishihara, Takuji Morimoto, Shougo Shimizu, Kenji Hashimoto, Toru Fujiwara. A Tractable Subclass of DTDs for XPath Satisfiability with Sibling Axes. In Philippa Gardner, Floris Geerts, editors, Database Programming Languages - DBPL 2009, 12th International Symposium, Lyon, France, August 24, 2009. Proceedings. Volume 5708 of Lecture Notes in Computer Science, pages 68-83, Springer, 2009. [doi]
Abstract is missing.