On the Issues of Social Law in Poland: A State of Research on the History of Social Insurance Law - Mazurkiewicz, Maciej Jan (. Rechtsgeschichte. - Frankfurt am Main : Vittorio Klostermann GmbH, 2002-. - Online-Ressource. - ISSN 2195-9617. - urn:nbn:de:hebis:30:epflicht-172326 24, 2016)