“Instalasi Dan Evaluasi Sistem Peringatan Dini Banjir Berbasis Sensor Ultrasonik HC-SR04 Dan Internet of Things (IoT)”. Sunan Kalijaga Journal of Physics, vol. 2, no. 2, Nov. 2020, pp. 64-71, https://doi.org/10.14421/physics.v2i2.2339.