“Hyperbaric 0.5% Bupivacain used in subarachnoid block which spread of anesthesia to cephalic at the different site of injection specially L 2-3, L 3-4, L 4-5 inter vertebral space”, TAJ: J of Teachers Assoc, vol. 28, no. 1, pp. 1–5, Dec. 2018, doi: 10.3329/taj.v28i1.39039.