Mohamed Moussa, M. E., H. G. Awad, H. S. Hamid, A. Abdellatif, and A. Sharaf. “A Comparative Study Between Femoral Nerve Block and Intravenous Ketamine for Pain Management During Positioning for Spinal Anesthesia in Elderly Patients With Femur Fracture”. Anaesthesia, Pain & Intensive Care, Vol. 26, no. 3, June 2022, pp. 297-03, doi:10.35975/apic.v26i3.1895.