ASSIMAKOPOULOU, A.; SALMAS, I.; KOUNAVIS, N.; BASTAS, A. I.; MICHOPOULOU, V.; MICHAIL , E. The Impact of Ammonium to Nitrate Ratio on the Growth and Nutritional Status of Kale. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, v. 47, n. 3, p. 848-859, 31 May 2019.