Marie Szymanowska: Serenade for piano and accompanying cello, composed for and dedicated to His Highness, Prince Anton Radziwiłł, Leipzig: Breitkopf and Härtel 1819, National Library of Warsaw/Bibliot...
Ryszard Mroziuk, handwritten note on the ‘P’ plaque given to Porta Polonica
‘Dar Pana Wiktora Opińskiego, więźnia i przymusowego robotnika’ (Donation from Mr Wiktor Opiński, prisoner and forced labourer) with the signet of the Polish Catholic Mission in Dortmund (front)