Filho, Moacyr Bernardini Dias. “Physiological Responses of Two Tropical Weeds to Shade. I. Growth and Biomass Allocation”. Pesquisa Agropecuaria Brasileira, vol. 34, no. 6, June 1999, pp. 945-52, doi:10.1590/S1678-3921.pab1999.v34.5275.