http://kawbtpskqu7rr3t6ecz4fyutpzq7jtblin3wv5vamneryu4nwenhkgyd.onion/mediawiki/index.php?title=Urba%C5%84ski,_Tadeusz&action=edit
He worked in the Pyrotechnic Laboratory of the Technical Institute of Armament of the Ministry of Military Affairs, operating in the "Missile" Ammunition Plant in Rembertów. In this unit, his collaborators were Zbigniew Kapuściński and Tadeusz Tucholski (later victims of the Katyn crime; moreover, the first of them taught him pilotage at the Warsaw Aeroclub in the 1930s).