Siregar, Helena, Azwin Lubis, M. Arif Nasution, Indra Kesuma Nasution, and Thamrin Tanjung. 2019. “Family Size and Marital Age”. Paediatrica Indonesiana 25 (5-6):107-11. https://doi.org/10.14238/pi25.5-6.1985.107-11.