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The ListSets verb will return a list of all harvestable OAI sets defined as LibraryCloud collections. At this time, the LibraryCloud ListSets verb does not support a resumptionToken, so the response will always include the first 10 collections only.
https://api.lib.harvard.edu/oai/?verb=ListSets
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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.
For this a ListRecords request in the Scarlet collection :-- https://api.lib.harvard.edu/oai/?verb=ListRecords&metadataPrefix=mods&set=scarlet, here -- this is how to use the resumption token to retrieve additional data beyond the first 10 items:
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