1919, "Boundary protection Ost"-army postal servicekarte with letter cancel "Freicorps Dohna 5. army corps" and cancellation adjusted army postal service postmark "K. D. Army postal service a 13. 5. 19" to Königshütte, dated Neuhammer with complete field post sender specification (army postal service 2136) . The Freicorps Dohna FOUGHT amongst other things in Upper Silesia against Polish franctireur, rare!