Kaczynski, Roman, Bogdan Korobko, Ievgen Vasyliev, and Anton Kivshyk. 2018. “Interaction of the Mortar Flow With of a Mortar Pump’s Valve Ball”. International Journal of Engineering & Technology 7 (4.8): 289-94. https://doi.org/10.14419/ijet.v7i4.8.27258.