EZEMA, R. A.; OMEJE, T. E.; ONUOHA, S. E.; NNAMANI, L. Short-Term Effects of Boiler Ash on Soil Microbial Population, Organic Carbon, Nitrogen Mineralization and Cowpea Biomass. New Perspectives in International Plant and Soil Research Vol. 1, p. 84-94, 22 ago. 2019.