Lancini, D., F. Belotti, M. Bottazzoli, E. Mercandelli, E. Moretti, R. Maroldi, and L. Rodella. “Ethmoidal Arteries Variability: An Anatomical and Radiological Study”. Italian Journal of Anatomy and Embryology, vol. 120, no. 1, Sept. 2015, p. 63, https://oajournals.fupress.net/index.php/ijae/article/view/4017.