Bluett, S., J. Hodgson, P. Kemp, and T. Barry. “Performance of Lambs and the Incidence of Staggers and Heat Stress on Two Perennial Ryegrass Cultivars over Three Summers in the Manawatu”. NZGA: Research and Practice Series, vol. 7, Jan. 1999, pp. 143-50, doi:10.33584/rps.7.1999.3383.