Anand, K.J.S. and Hickey, P.R. 1987. Pain and its effects in the human neonate and fetus. New England Journal of Medicine 317(21):1321–1329.

Anon. 1990. Neonatal pain and distress. In, Pain Research & Clinical Management, vol. 2, ed. K.J.S. Anand and P.A. McGrath. Amsterdam: Elsevier.

Berry, F.A. and Gregory, G.A. 1987. Do premature infants require anaesthesia for surgery? Anesthesiology 67:291–293.

Craig, K.D., Whitfield, M.F., Grunau, R.V.E., Linton, J. and Hadjistavropoulos, H.D. 1993. Pain in the preterm neonate: behavioural and physiological indices. Pain 52:287–299.

Fitzgerald, M. 1987. Pain and analgesia in neonates. Trends in Neurosciences 10:344–346.

Fitzgerald, M. 1991. Development of pain mechanisms. British Medical Bulletin 47: 667–675.

Fitzgerald, M. 1995. Fetal pain: an update of current scientific knowledge. A paper for the Department of Health.

Grunau, R.V.E., Johnston, C.C. and Craig, K.D. 1990. Neonatal facial and cry responses to invasive and non-invasive procedures. Pain 42:295–305.

Humphrey, T. 1964. Some correlations between the appearance of human fetal reflexes and the development of the nervous system. Progress in Brain Research 4: 93–135.

Kuljis, R.O. 1994. Development of human brain: the emergence of the neural substrate for pain perception and conscious experience. In: The Beginnings of Human Life, pp. 49–56, ed. F.K. Beller and R.F. Weir. Dordrecht, The Netherlands: Kluwer Academic Publishers.

McCullagh, P. 1996. Fetal Sentience. A paper published by the All Party Parliamentary Pro Life Group.

Ownes, M.E. 1984. Pain in infancy: Conceptual and methodological issues. Pain 20:213–230.

Teixeira, J., Fogliani, R., Giannakoulopoulos, X., Glover, V. and Fisk, N.. 1996. Fetal haemodynamic stress response to invasive procedures. Lancet 347: 624.