1. Structural joints: a primitive for efficient XML query pattern matching;Al-Khalifa,2002
2. Minimization of tree pattern queries;Amer-Yahia,2001
3. M. Benedikt, W. Fan, and G. M. Kuper. Structural properties of XPath fragments. In ICDT, pages 79–95, 2003.
4. XQuery 1.0: An XML query language;Boag,2003
5. Holistic twig joins: optimal xml pattern matching;Bruno,2002