Uzoh, I., and O. . Babalola. “Review on Increasing Iron Availability in Soil and Its Content in Cowpea (<i>Vigna unguiculata</I>) by Plant Growth Promoting Rhizobacteria”. African Journal of Food, Agriculture, Nutrition and Development, vol. 20, no. 3, May 2020, pp. 15779-9, doi:10.18697/ajfand.91.18530.