1. , & (1988). Compression of concordances in full-text retrieval systems. In (Ed.), Proceedings of the 11th ACM-SIGIR Conference, Grenoble, 597–612.
2. , , & (1987). Improved techniques for processing queries in full-text systems. In (Eds.), Proceedings of the 10th ACM-SIGIR Conference, New Orleans, 306–315.
3. , (Eds.). (1999). World Wide Web Consortium, XML Path Language (XPath), Version 1.0, W3C Recommendation, 16 November 1999,