Berbara, R. L. L., Freire, L. R. and Fernandes, M. S. (1999) “Influence of arbuscular mycorrhiza fungi on the nutrition of okra plant”, Pesquisa Agropecuaria Brasileira, 34(9), pp. 1645–1653. doi: 10.1590/S1678-3921.pab1999.v34.5408.