We would like to thank the whole UMDL team. Special thanks to the Conspectus Search and Retrieval group (Amy Warner, Elke Rudensteiner, Anisoara Nica, Steve Kirk, Spencer Thomas, Fritz Freiheit, Eric Glover, Edmund Durfee, and José Vidal) for coming up with the techniques that the TPA uses for answering a query. This work was supported by the NSF/ARPA/NASA Digital Library initiative.