1. Life at death. A scientific investigation of the near-death experience;Ring,1980
2. Dying to live: science and the near-death experience;Blackmore,1993
3. Transformed by the light;Morse,1990
4. Syncope and near-death experience;Lempert;Lancet,1994
5. Near-death experience: analogous to other stress induced physiological phenomena;Appelby;BMJ,1989