M. F. C. Lina et al., “Transformational Leadership of School Heads and the Instructional Performance of Public School Teachers: A Convergent Parallel Mixed-Methods Study”, Int. J. Sustain. Integr. Stud., vol. 1, no. 4, pp. 289–295, Nov. 2026, doi: 10.65339/ijsis.V1.I4.283.