Bustam, M R. “Interactional Meaning of Systemic Functional Multimodal Discourse Analysis on World Health Day 2020 Poster Related to Covid-19 Issue”. Proceeding of International Conference on Business, Economics, Social Sciences, and Humanities, vol. 3, Mar. 2023, pp. 781-90, https://doi.org/10.34010/icobest.v1i.243.