Kaldashev, Tsvetan, and Petar Hadjiiski. “STUDY OF ERROR ESTABLISHMENT IN MILLING MACHINES WITH 5 AXES”. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, vol. 3, June 2019, pp. 81-83, https://doi.org/10.17770/etr2019vol3.4187.