1. Associate Professor of Anaesthesia, Department of Anaesthesia, Faculty of Medicine, Dalhousie University, Halifax, N. S. Canada, B3H 2Y9. Research Fellow in Obstetric Anesthesia, Bowman Gray School of Medicine
2. Professor and Chief, Section of Obstetric/Gynecologic Anesthesia, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina 27103
3. Associate Professor, Department of Anesthesia, Bowman Gray School of Medicine of Wake Forest University, Winston- Salem. North Carolina 27103