Marzhan Y. Kizatova, Madina Zh. Sultanova, Alexander Y. Borovsky, Nurzhan Zh. Muslimov, Zhibek A. Nokusheva, Yevgeny S. Aitzhanov. Mathematical Planning of a Multi-Factor Experiment and Optimization of the Feed Extrusion Process. IJAST 2020, 29, 1369 - 1382.