Ruengsitagoon, Wirat, Rutchayaporn Anorat, and Pradit Pearruksa. “Determination of lead, arsenic, cadmium, copper and zinc in traditional medicines by atomic spectrophotometry(Thai)”. Asia-Pacific Journal of Science and Technology 10, no. 2 (April 20, 2017): 135–140. accessed March 7, 2026. https://so01.tci-thaijo.org/index.php/APST/article/view/84018.