Volkov, I.; Rudoy, I.; Freud, T.; Sardal, G.; Naimer, S.; Peleg, R.; Press, Y. (2009). Effectiveness of Vitamin B12 in Treating Recurrent Aphthous Stomatitis: A Randomized, Double-Blind, Placebo-Controlled Trial. The Journal of the American Board of Family Medicine, 22(1), 9–16.
doi:10.3122/jabfm.2009.01.080113