Hasan, S., A. . Nurdin, and R. Manan. “VIBRATION SPECTRUM ANALYSIS FOR FAULT DIAGNOSIS OF BALL BEARING IN CONDENSATE TRANSFER PUMP”. Jurnal Rekayasa Mesin Dan Inovasi Teknologi, vol. 2, no. 1, June 2021, pp. 106-12, http://jurnal.ftm.uniba-bpn.ac.id/index.php/REMIT/article/view/28.