REGASSA, C.; TOLCHA, T.; GOMORO, K.; MEGERSA, N. Determination of Residue Levels of DDT and Its Metabolites in Khat and Cabbage Samples using QuEChERS Sample Preparation Method Combined with GC-MS Detection. Ethiopian Journal of Science and Sustainable Development, v. 7, n. 1, p. 44-53, 10 jan. 2020.