Authors: Ledgard, SF Sprosen, MS Penno, JW Rajendram, GS

Citation: Sf. Ledgard et al., Nitrogen fixation by white clover in pastures grazed by dairy cows: Temporal variation and effects of nitrogen fertilization, PLANT SOIL, 229(2), 2001, pp. 177-187

Authors: McCall, DG Clark, DA Stachurski, LJ Penno, JW Bryant, AM Ridler, BJ

Citation: Dg. Mccall et al., Optimized dairy grazing systems in the northeast United States and New Zealand. I. model description and evaluation, J DAIRY SCI, 82(8), 1999, pp. 1795-1807

Authors: Ledgard, SF Penno, JW Sprosen, MS

Citation: Sf. Ledgard et al., Nitrogen inputs and losses from clover/grass pastures grazed by dairy cows, as affected by nitrogen fertilizer application, J AGR SCI, 132, 1999, pp. 215-225

Authors: Ledgard, SF Crush, JR Penno, JW

Citation: Sf. Ledgard et al., Environmental impacts of different nitrogen inputs on dairy farms and implications for the Resource Management Act of New Zealand, ENVIR POLLU, 102, 1998, pp. 515-519