Nwauche, C., A. Eneh, C. Pughikumo, and I. Chijioke-Nwauche. “ABO and Rhesus Blood Groups in Mothers and Their Newborns in Port Harcourt, Nigeria”. Port Harcourt Medical Journal, vol. 6, no. 4, Feb. 2013, pp. 455-9, doi:10.4314/phmedj.v6i4.