Pertiwi, Syuhada. " DESIGN AND MAKING FORMALIN LEVEL DETECTION TOOLS IN FOOD USING ARCHUINO UNO-BASED HCHO SENSORS WITH NOTIFICATION THROUGH SMS." Kumpulan Karya Ilmiah Mahasiswa Fakultas sains dan Tekhnologi [Online], 1.1 (2019): 310. Web. 1 Oct. 2023