Yasser, Muhammad, and Muhammad Badai. “KAREKTERISASI EKSTRAK ETANOL UBI JALAR UNGU (Ipomea Batatas L) MENGGUNAKAN SPEKTROSKOPI INFRARED”. Cokroaminoto Journal of Chemical Science, vol. 1, no. 1, Aug. 2019, pp. 4-6, https://science.e-journal.my.id/cjcs/article/view/11.