1. Pain mechanisms: A new theory;Melzack;Science,1965
2. Electrical stimulation of the human nervous system for the control of pain;Gybels,1979
3. Transcutaneous electrical stimulation in the treatment of chronic and acute pain;Long,1976
4. Dermatitis associated with transcutaneous electric nerve stimulation;Fisher;Cutis,1978
5. Allergic contact sensitivity to propylene glycol in a lubricant jelly;Fisher;Arch Dermatol,1979