Abraham, E. M.; Kyriazopoulos, A.; Parissi, Z. M.; Sklavou, P.; Tsiouvaras, C. N. Defoliation Frequency Effects on Winter Forage Production and Nutritive Value of Different Entries of Agropyron Cristatum (L.) Gaertn. Span. j. agric. res. 2010, 8, 703-712.