M. A. S. . Jawwad, I. W. . Murti, A. M. . Khasanah, and P. S. A. . Sitogasa, “Handwash Soap Production by Recycling Used Cooking Oil to Empower a Boarding School in Surakarta”, Nusantara Sci. Tech. Proc., vol. 2022, no. 24, pp. 326–329, May 2022, doi: 10.11594/nstp.2022.2449.