هترة ع., سلامة ا., and الضاهر ن. “Improving Mechanical Properties (Impact Strength and Wear Resistance) of Drilling Teeth Steel and Breakers Hammersr”. Tishreen University Journal -Engineering Sciences Series, vol. 43, no. 2, May 2021, http://www.journal.tishreen.edu.sy/index.php/engscnc/article/view/10552.