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http://sru.gbv.de/gvk?version=1.1&operation=searchRetrieve&query=pica.all%3Deasterall%3Dreformation&maximumRecords=5&sortKeys=year,,1
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http://sru.gbv.de/gvk?version=1.2&operation=searchRetrieve&query=pica.all%3Deasterall%3Dreformation+sortby+year%2Fdescending&maximumRecords=5
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