A. Q. Rahman, R. K. Al-Kamali, K. F. Dizaye, N. R. Hussein, and R. A. Mohammedammen, “Evaluation of The Topical Effect of Calendula Officinalis Oral Paste in The Treatment of Recurrent Aphthous Stomatitis: A Randomized Double-Blind Controlled Trial”, EDJ, vol. 8, no. 2, pp. 171–180, Dec. 2025.