Shahab, Aliyah, and Sulton Amna. “EFFICIENCY ANALYSIS OF FIRE TUBE BOILER TYPE AT REFINERY UTILITY UNIT CENTER FOR OIL AND GAS HUMAN RESOURCES DEVELOPME”. Jurnal Cakrawala Ilmiah, vol. 2, no. 7, Mar. 2023, pp. 3109-18, doi:10.53625/jcijurnalcakrawalailmiah.v2i7.5401.