Franco, A.A. and Döbereiner, J. 2014. Interference of calcium and nitrogen in symbiotic nitrogen fixation of two bean varieties (<i>Phaseolus vulgaris</i> L.). Pesquisa Agropecuaria Brasileira. 3, 1 (Apr. 2014), 223–227. DOI:https://doi.org/10.1590/S1678-3921.pab1968.v3.17941.