Mamuda, A. A., M. K. Abubakar, M. G. Taura, M. A. Kabir, I. S. Yusuf, and L. H. Adamu. “Extadigits: An Unusual Presentation”. International Journal of Research in Medical Sciences, vol. 1, no. 4, Jan. 2017, pp. 607-10, https://www.msjonline.org/index.php/ijrms/article/view/2686.