Isa Osu, U. et al. 2018. Heavy metals assessment of soils in and around Kama-Otto and Kwotto artisanal mining of mica, cassiterite and tantalite in Nasarawa state, Nigeria. International Journal of Advanced Chemistry. 6, 2 (Jul. 2018), 135–139. DOI:https://doi.org/10.14419/ijac.v6i2.10630.