https://kuryerpolski.us/en/Page/view/czym-byl-przedwojenny-korpus-ochrony-pogranicza
What was the pre-war Border Protection Corps? - Kuryer Polski [en]
The Border Protection Corps (Korpus Ochrony Pogranicza, KOP) was established one hundred years ago, on 17 September 1924. For exactly fifteen years, until the...
border protection corpskuryer polskiprewar