Ratu Ayu, W. D. “Analysis of English Code Switching by Lecturer in Public Speaking Class of English Education Study Program at Muhammadiyah Kotabumi University”. Griya Cendikia, vol. 8, no. 1, Feb. 2023, pp. 206-1, https://juma.umko.ac.id/index.php/griya-cendikia/article/view/462.