Sulaiman, Siti Sarah, and Rosli Ahmad. “Effect of Yttrium on Microstructure and Hardness Properties of Aluminium LM30 Alloy”. Research Progress in Mechanical and Manufacturing Engineering, vol. 4, no. 1, Aug. 2023, pp. 359-64, https://publisher.uthm.edu.my/periodicals/index.php/rpmme/article/view/9287.