Pinto, A. V., A. X. Chakiath, P. Dasari, V. Reddy, S. George, and N. Shankar. “Direction of Umbilical Cord Twist and Its Characteristics – a Pilot Study”. International Journal of Medical Students, vol. 1, no. 3, Dec. 2013, pp. 120-2, doi:10.5195/ijms.2013.218.