«Maternal, newborn and child health (MNCH) services utilization: A comparative case study of tertiary and primary health care facilities in Cross River State». (2021) African Journal of Biomedical Research, 24(1), с. 81–92. доступний у: https://ojshostng.com/index.php/ajbr/article/view/1154 (дата звернення: 1 Травень 2026).