Markov, O., Zlygoriev, V., Gerasimenko, O., Hrudkina, N. and Shevtsov, S. 2018. Improving the quality of forgings based on upsetting the workpieces with concave facets. Eastern-European Journal of Enterprise Technologies. 5, 1 (95) (Sep. 2018), 16–24. DOI:https://doi.org/10.15587/1729-4061.2018.142674.