A general purpose client to work with any 'OAI-PMH' (Open Archives Initiative Protocol for 'Metadata' Harvesting) service. The 'OAI-PMH' protocol is described at <http://www.openarchives.org/OAI/openarchivesprotocol.html>. Functions are provided to work with the 'OAI-PMH' verbs: 'GetRecord', 'Identify', 'ListIdentifiers', 'ListMetadataFormats', 'ListRecords', and 'ListSets'.
copied from cf-staging / r-oai