Sembiring, Meriah, Iskandar Iskandar, Amir Syarifuddin, and Bistok Saing. 2017. “Denver Developmental Screening Test in Two-Year Old Infants Delivered by Vacuum Extraction”. Paediatrica Indonesiana 41 (1-2), 27-32. https://doi.org/10.14238/pi41.1.2001.27-32.