Narong, P., J. Petsom, and K. Rattanaponglayka. “Efficiency of heavy metal adsorption by entrapped Saccharomyces cerevisiae on coconut fibers in upflow anaerobic filter system”. Engineering and Applied Science Research, vol. 26, no. 4, Feb. 2013, pp. 37-44, https://ph01.tci-thaijo.org/index.php/easr/article/view/6321.