Parnia S; Waller D. G; Yeates R; Fenwick P. (2001). "A Qualitative and Quantitative Study of the Incidence, Features and Aetiology of Near-Death Experiences in Cardiac Arrest Survivors". Resuscitation. 48 (2): 149–156. doi:10.1016/s0300-9572(00)00328-2. PMID11426476.
Parnia S; Waller D. G; Yeates R; Fenwick P. (2001). "A Qualitative and Quantitative Study of the Incidence, Features and Aetiology of Near-Death Experiences in Cardiac Arrest Survivors". Resuscitation. 48 (2): 149–156. doi:10.1016/s0300-9572(00)00328-2. PMID11426476.