Can anybody here point me to some instructions on how to export subsets of MARC records to a file from VTLS's Virtua integrated library system?

As a part of the "Catholic Portal", I harvest sets of MARC records from our alliance's membership. These records are expected to be exported from member integrated library systems and accessible at the other end of a URL. I have an alliance member who has lost their systems librarian, and thus not sure how to do the necessary export. Can somebody here show me some instructions on how to accomplish this task.

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Eric Lease Morgan