1. F. J. Browne (1944 ): Antenatal and postnatal care . 5th ed. Churchill, London, p.236 .
2. Roentgen Visualization of the Placenta by Soft Tissue Technique
3. EXTERNAL CEPHALIC VERSION
4. G. F. Gibberd (1949 ): Short textbook of midwifery . 4th ed. Churchill, London, p.270 .
5. C. M. Marshall (1939 ): Caesarean section . Wright, Bristol, pp.40 , 41.