Lianzi, L., N. Sartjinpong, and P. Rodchangphuen. “A Study the Hakka Folk Song for Writing Hakka Folk Songs Vocal Guidebook”. Journal of Modern Learning Development, vol. 9, no. 12, Dec. 2024, pp. 503-15, https://so06.tci-thaijo.org/index.php/jomld/article/view/275631.