«Maternal, Newborn and Child Health (MNCH) Services Utilization: A Comparative Case Study of Tertiary and Primary Health Care Facilities in Cross River State». African Journal of Biomedical Research, т. 24, вып. 1, январь 2021 г., сс. 81-92, https://ojshostng.com/index.php/ajbr/article/view/1154.