Camargo, Carlos Eduardo de Oliveira, et al. “Influence of Different Iron Levels in Nutrient Solution on the Primary Root Growth of Wheat”. Pesquisa Agropecuaria Brasileira, vol. 24, no. 12, Apr. 2014, pp. 1529-35, doi:10.1590/S1678-3921.pab1989.v24.16615.