Pranata, A., R. Septiari, and D. W. Lestarining B. “PERANCANGAN KONSEPTUAL SAFETY HELMET 4 IN 1 BERDASARKAN KEBUTUHAN PEKERJA MANUFAKTUR BAHAN BANGUNAN”. Jurnal Valtech, Vol. 9, no. 2, Oct. 2026, pp. 152-7, doi:10.36040/valtech.v9i2.22370.