García, Mesías M., and Frescia M. Madueño. “Determination of Heavy Metals (Lead and Cadmium) in Lettuce (Lactuca Sativa) in Markets of Metropolitan Lima”. Ciencia E Investigación, vol. 21, no. 2, Mar. 2019, pp. 19-23, https://doi.org/10.15381/ci.v21i2.15852.