Haq, Ayunita, et al. “Accuracy of HC-SR04 Ultrasonic Servo in Servo-Scanned 2D Ranging”. Prisma Sains : Jurnal Pengkajian Ilmu Dan Pembelajaran Matematika Dan IPA IKIP Mataram, vol. 14, no. 3, June 2026, pp. 1417-31, doi:10.33394/j-ps.v14i3.19813.