... Up: VO Resources . ... Monkewitz, S. & Good, J. 2003, in ASP Conf. ... We describe the architecture of a general cross-comparison engine capable of spatially matching sources in one astronomical source catalog with those in another. ... Support is provided for common catalog formats and data sources (e.g. local disk, database servers), and the addition of support for custom data formats and sources is simplified by the modular architecture employed. ... Data Access: . ... Source List Processing: . ...