1. S. Abiteboul and P. Buneman,Data on the Web: From Relations to Semi-structured Data and XML(1999).
2. R. Alur, S. Chaudhuri and P. Madhusudan, A fixpoint calculus for local and global program flows, Symposium on Principles of Programming Languages, POPL 2006 (2006) 153–165.
3. R. Alur, S. Chaudhuri and P. Madhusudan, Languages of nested trees, Computer-Aided Verification, CAV 2006 (2006) 329–342.
4. Rajeev Alur and P. Madhusudan, Visibly pushdown languages, Chicago, USA. 36th ACM symposium on Theory of Computing (2004) 202–211.
5. M. Bojanczyck and T. Colcombet, Tree-walking automata cannot be determinized. ICALP (2004) 246–256.