SakhoshkoМ.М., M.I. Kravchenko, V.M. Yatsenko, and I.O. Kolosok. 2019. “Development of the Leaf Area and the Productivity Structure of the Sunflower Hybrids in the North-Eastern Forest-Steppe of Ukraine”. Bulletin of Sumy National Agrarian University. The Series: Agronomy and Biology, no. 1-2(35-36) (July), 33-39. https://doi.org/10.32845/agrobio.2019.1-2.5.