“Kalibrasi Sensor Mq-7 Dan Mq-136 Terhadap Sensor Ecom J2kn Pro Sebagai Alat Pengukur Gas Buang (Co Dan So2) Pada Proses Roasting Kopi: Sensor Calibration of MQ-7 and MQ-136 to Ecom J2kn Pro Sensor as Exhaust Gas Meter (CO and SO2) in Coffee Roasting Process” (2019) Talenta Conference Series: Science and Technology (ST), 2(2). doi:10.32734/st.v2i2.491.