Dang, T. (2019). DETERMING LEAD IN SOIL BY EXTRACTION-PHOTOMETRIC IN CAO LANH CITY, DONG THAP PROVINCE. TRA VINH UNIVERSITY JOURNAL OF SCIENCE; ISSN: 2815-6072; E-ISSN: 2815-6099, 7(25), 56-59. https://doi.org/10.35382/18594816.1.25.2017.121