Justification of optimal design and technological parameters of needle discs of the combined working bodyAlexander M. Petrov, Sergey A. Ivanayskiy, Mikhail A. Kanaev, Oleg M. Parfyonov and Maxim S. IvanayskiyBIO Web Conf., 17 (2020) 00016DOI: https://doi.org/10.1051/bioconf/20201700016