Nolasco, Marita Nimiah P. “SPED Teachers’ Extent of Implementing Picture Exchange Communication System: It’s Effect on the Functional Communication Skills of Learners With Down Syndrome”. International Journal of Multidisciplinary: Applied Business and Education Research, vol. 3, no. 9, Sept. 2022, pp. 1812-20, https://doi.org/10.11594/ijmaber.03.09.21.