Costa, E.M. da et al. 2014. Growth and yield of the cowpea cultivar BRS Guariba inoculated with rhizobia strains in southwest Piauí. Semina: Ciências Agrárias. 35, 6 (dez. 2014), 3073–3084. DOI:https://doi.org/10.5433/1679-0359.2014v35n6p3073.