Simpen, Nengah, 		Winaya, IN. Suprapta, 		Subagia, ID.G. Ary, AND 		Suyasa, IW. Budiarsa.
" Solid Catalyst in Esterification and Transesterification Reactions for  Biodiesel Production: A Review" <em>International Journal of Engineering and Emerging Technology</em> [Online], Volume 5 Number 2 (15 December 2020)