Syahri, B., F. Prasetya, R. Refdinal, and S. Syahrial. “Effect of Cutting Speed on Milling Process on Surface Roughness of ST-37 Steel Material Workpiece”. INVOTEK: Jurnal Inovasi Vokasional Dan Teknologi, Vol. 21, no. 1, Feb. 2021, pp. 19-26, doi:https://doi.org/10.24036/invotek.v21i1.766.