M. B. Naiborhu, M. S. Sianipar, K. H. B. Bukit, S. G. Silitonga, W. W. S. Hulu, and M. Girsang, “Poetry as moral education: representation of maternal love and gratitude in Miller Mottla’s ‘thank you Mom’”, IJE, vol. 5, no. 1, pp. 111–114, Feb. 2026.