Mehraj, A. et al. 2020. TO COMPARE THE INCIDENCE OF POST DURAL PUNCTURE HEADACHE WITH PENCIL POINT 25 GAUGE WHITACRE VERSE CUTTING 25 GAUGE QUINCKE SPINAL NEEDLE IN PATIENTS FOR C SECTION UNDER SPINAL ANAESTHESIA. Pakistan Armed Forces Medical Journal. 70, 6 (Dec. 2020), 1897–1901.