In Monitor Prawniczy (No. 19/2017) an article entitled "The legal limits of processing of personal data for the purposes of direct marketing without the consent of the data subject - the perspective of Polish and German law in the light of the General Data Protection Regulation" by Katarzyna Reszczyk-Król
The author discusses the permissible limits of processing of personal data for marketing purposes without the consent of the data subject in Poland and Germany, with particular emphasis on the impact of RODO on the national legislations. The text also addresses the issues of how the entrepreneurs can lawfully direct specific advertising content to the recipients.
The article is available here