Purnawan, D., J. Hutagalung, and S. Azmi. “Penerapan Metode Certainty Factor Dalam Mendiagnosa Penyakit Kehamilan Berbasis Web”. Building of Informatics, Technology and Science (BITS), Vol. 4, no. 2, Sept. 2022, pp. 614-23, doi:10.47065/bits.v4i2.2039.