Mykhalko , O., and M. Povod. 2019. “Seasonal Dependence of Sow Productivity of Danish Origin from Constructive Features Ventilation Systems During Hair and Lactation”. Bulletin of Sumy National Agrarian University. The Series: Livestock, no. 3 (38) (September), 78-90. https://doi.org/10.32845/bsnau.lvst.2019.3.10.