“Development of a bioassay to quantify the ricin toxin content of castor bean (Ricinus communis L.) seeds - doi: 10.4025/actasciagron.v34i4.11284”, Acta Sci. Agron., vol. 34, nº 4, p. 397–402, dez. 2011, doi: 10.4025/actasciagron.v34i4.11284.