Calderon, A. L. R. ., H. K. . Mandabob, J. M. G. Maroto, and C. J. O. . Syting. “Exploring Language Proficiency Enhancement Trainings of Call Center Agents: Unveiling BPO Trainer Strategies from Agents’ Standpoints”. International Journal Corner of Educational Research, vol. 3, no. 3, Mar. 2025, pp. 147-62, doi:10.54012/ijcer.v3i3.354.