1. Referred pain from somatic and visceral structures;Procacci;Curr Rev Pain,1999
2. Visceral pain;Cervero;Lancet,1999
3. Referred muscle pain and hyperalgesia from viscera: clinical and pathophysiological aspects;Giamberardino;Basic Appl Myol,2004
4. Pain-autonomic interactions: a selective review;Benarroch;Clin Auton Res,2001
5. Bonica’s management of pain;Loeser,2001