Sun, Hui, Jie Gao, Dan Li, and Bing Li. 2021. “Observations on the Clinical Efficacy of RhaFGF Combined With Vitamin B Complex for Patients With Severe Recurrent Aphthous Ulcer: Treatment of Severe Recurrent Aphthous ulcer (RAU)”. Pakistan Journal of Medical Sciences 37 (7). https://doi.org/10.12669/pjms.37.7.4364.