The Role of Mixed Alkaline Earth Effects on The Elastic Properties of xBaF2–(50 – x)CaF2–50B2O3 Fluoroborate Glasses: Comparative Analysis of Ultrasonic Measurements and Theoretical Models . Mal. J. Fund. Appl. Sci. 2025;21(6):2825-2843. doi:10.11113/mjfas.v21n6.3892