Stumpf, Lizete, et al. “Physical Condition and Root Development of Grasses in a Constructed Minesoil After Coal Mining”. Pesquisa Agropecuaria Brasileira, vol. 51, no. 9, Oct. 2016, pp. 1078-87, doi:10.1590/S1678-3921.pab2016.v51.22200.