^Ramirez-Bahena, M. H. (2009). "Bradyrhizobium pachyrhizi sp. nov. and Bradyrhizobium jicamae sp. nov., isolated from effective nodules of Pachyrhizus erosus". International Journal of Systematic and Evolutionary Microbiology. 59 (8): 1929–1934. doi:10.1099/ijs.0.006320-0. PMID19567584.