[1]
I. A. A. Putri, F. D. Sitania, and Y. Sukmono, “Preventive Maintenance Analysis to Improve the Readiness of Heavy Equipment Hydraulic Excavator Liebherr R9250 & R9350 with Six Sigma Method at PT. XYZ”, IJIEM, vol. 5, no. 3, pp. 701–711, Mar. 2025.