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https://api.lib.harvard.edu/oai/?verb=ListMetadataFormats (works)
https://api.lib.harvard.edu/oai/?verb=ListMetadataFormats&identifier=990007968560203941 (why doesn't this work?)
Resumption tokens
The OAI requests for ListSets, ListRecords, and ListIdentifiers retrieve 10 results at a time, so the repeated use of a resumptionToken in the request URL is needed to retrieve the full amount of data.
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