de Troiani, R., T. Sánchez, N. Reinaudi, and L. de Ferramola. “Optimal Sowing Dates of Three Species of Grain-Bearing Amaranth in the Semi-Arid Argentine Pampa”. Spanish Journal of Agricultural Research, Vol. 2, no. 3, Sept. 2004, pp. 385-91, doi:10.5424/sjar/2004023-93.