Grünwaldt, J. M. ., P. . Felker, J. C. . Guevara, and E. G. . Grünwaldt. “Opuntia Ellisiana Griffiths As Livestock Feed in Areas Similar to Usda Cold Hardiness Zones 6-7”. Revista De La Facultad De Ciencias Agrarias Uncuyo, vol. 52, no. 1, June 2020, pp. 372-90, https://revistas.uncu.edu.ar/ojs3/index.php/RFCA/article/view/3078.