Sholihat, W. “ THE INFLUENCE OF SALES VOLUME AND OPERATING COSTS ON PROFIT AT PT. SINAR REKSA KENCANA (SRK) RAKIT KULIM DISTRICT, INDRAGIRI HULU REGENCY”. Journal of Industrial Engineering & Management Research, Vol. 1, no. 1b, June 2020, pp. 219-31, doi:10.7777/jiemar.v1i1b.330.