KRYSZAK, A.; KLARZYNSKA, A.; KRYSZAK, J.; STRYCHALSKA, A.; MACKOWIAK, L. Influence of Variability of Ryegrass Meadow Soil Conditions on their Natural and Utilization Values. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, v. 40, n. 1, p. 163-169, 14 May 2012.