Ghim Hock Ong, Chee Kong Yap, Maziah Mahmood, and Suhaimi Hamzah, “Barium Levels in Soils and Centella asiatica”, tlsr, vol. 24, no. 1, pp. 55–70, Jul. 2013, Accessed: Apr. 03, 2025. [Online]. Available: https://ejournal.usm.my/tlsr/article/view/tlsr_vol24-no-1-2013_6