“Evaluation of Supplier Performance at PT. XYZ Using a Combined Method of Purchasing Portofolio Matrix (PPM) and Supplier Potential Matrix (SPM)”. G-Tech: Jurnal Teknologi Terapan, vol. 9, no. 2, Apr. 2025, pp. 968-77, https://doi.org/10.70609/gtech.v9i2.6822.