Omelkovych , S., A. Shuliar, and A. Shuliar. “Evaluation of Qualitative Characteristics of a cow’s Milk and Their Correlation With the Period of Lactation”. Bulletin of Sumy National Agrarian University. The Series: Livestock, no. 2 (45), May 2021, pp. 108-12, doi:10.32845/bsnau.lvst.2021.2.16.