Marpaung, M., A. S. Sitio, and B. Sinaga. “PKM : Pelatihan Public Speaking Bagi Penyandang Tuna Netra SLB-A Karya Murni Medan Johor”. Jurnal Ekonomi, Vol. 9, no. 1, Juni, June 2020, pp. 19-21, https://jeko.iocspublisher.org/index.php/jek/article/view/3.