H. Mai, J. .-L. Maeghtb, V. H. Bui and C. Valentin, Assessment of heavy metal concentrations and its potential eco-toxic effects in soils and sediments in Dong Cao catchment, Northern Vietnam, Vietnam J. Earth Sci. 42 (2020) 187–204. DOI: https://doi.org/10.15625/0866-7187/42/2/15046.