Amr Sobhy, Radwa Tarek Mohamed, Gihan seif, Manal mohamed kamal shams, Adham Magdy Haggag, Abd El-Aziz A. Abd EL-Aziz. "Ultrasound-guided sacral multifidus plane block versus caudal epidural block for postoperative analgesia in pediatric hypospadias surgery: A randomized double-blind controlled trial." PLoS ONE, 2026. doi:10.1371/journal.pone.0353110