Silveira, P.M. da and Gonzaga, A.C. de O. (2017) “Portable chlorophyll meter can estimate the nitrogen sufficiency index and levels of topdressing nitrogen in common bean”, Pesquisa Agropecuária Tropical [Agricultural Research in the Tropics], 47(1), pp. 1–6. doi:10.5216/pat.v47i1.42128.