This WWII paper model is a BD-41 armored self-propelled railroad car, the papercraft created by Lubosch. The scale of the paper model is in 1:25. BD-41 was designed from December 1941 to January 1942 in Voitovich plant in Moscow. The hull was welded from sheets with a thickness of 8-10 mm. Tower with a 37 mm cannon and 7.62 mm machine gun DT comes with two towers of T-26 (M1931). The crew consisted of 4-6 persons.
You can download the papercraft model here: WWII BD-41 Armored Railroad Car Free Paper Model Download